A. Cheney
Sabre Inc.
December 2009
Obsoletes: 1939, 3501, 5322

                    Mail Markup Language - Version 1.1





   Distribution, reproduction, and transmission of this document, and
   the language contained herein, is unlimited WITHOUT owner or author
   consent.

   Mail Markup Language (MML) is the intellectual property (IP) of Sabre
   Inc (OWNER).  MML contains features that are patent pending as well
   as additional features that are disclosed and unprotected novelties.
   Removal or omission of entire features, of specifically the language
   or its containing standard, may represent a conflict of IP unless
   approval for such removal is granted from an authorized agent of the
   OWNER.  Version 1.1 of MML claims derivation from MML Version 1.0.
   Any protection or novelty implied or expressed by MML Version 1.0
   must be applied upon Version 1.1 as a derivative work of equal scope,
   intention, and application as may be defined by the utility
   protection.


























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Abstract
   Mail Markup Language (MML) is a simple tag based markup language used
   to describe and structure data in a document intended to represent
   communication across the medium of email.  MML is written in W3C XML
   Schema language.  All MML documents are XML documents that conform to
   the MML schema.  This specification intends to replace RFC 5322.

IANA Considerations
   This specification requests the registration of a namespace and two
   MIME types.  The namespace name requested is MML.  A static URI
   pointed to the location of the mail.xsd as hosted by a standards body
   is also requested for mapping to the requested namespace name.  That
   URI would become the value of the MML:schemaLocation attribute.  The
   MIME type application/mail+xml is also requested.  The
   application/mail+xml MIME type will be used to identify a MML
   document for processing as mail over any standard mail protocol.




































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Table of Contents

1. Introduction ....................................................   5
   1.1. Scope ......................................................   5
   1.2. Requirements ...............................................   6
   1.3. Terminology ................................................   6
2. Philosophy of Design ............................................   7
   2.1. Structure ..................................................   7
   2.2. Syntax Simplicity and Understandability ....................   8
   2.3. Semantics ..................................................   8
   2.4. Accessibility ..............................................   9
   2.5. Presentation ...............................................   9
   2.6. Security ...................................................   9
3. External Technologies ...........................................  10
   3.1. Extensible Markup Language (XML) and W3C XML Schema ........  10
   3.2. XForms .....................................................  10
   3.3. Accessible Rich Internet Applications (ARIA) ...............  10
   3.4. Resource Document Framework (RDF) ..........................  10
   3.5. Stylesheet Technologies ....................................  11
   3.6. Behaviors and Scripting ....................................  11
   3.7. Public Key Infrastructure (PKI) ............................  11
   3.8. Uniform Resource Identifier (URI) ..........................  11
   3.9. Multipurpose Internet Mail Extensions (MIME) ...............  11
4. Processor Roles .................................................  11
   4.1. Processor Requirements and Constraints .....................  12
      4.1.1. Validation ............................................  12
      4.1.2. RFC 2822/5322 Conformance .............................  12
      4.1.3. Session Separation and Presentation ...................  12
      4.1.4. Session Preservation ..................................  13
      4.1.5. Character Set .........................................  13
      4.1.6. Session Timestamp .....................................  13
      4.1.7. URI Resolution ........................................  13
      4.1.8. MIME Execution Restriction ............................  13
      4.1.9. Caching ...............................................  13
      4.1.10. Local Processing .....................................  13
      4.1.11. MIME Catalogue .......................................  14
      4.1.12. From and Reply-to Tags ...............................  14
      4.1.13. Attachments ..........................................  14
      4.1.14. Processing of <plain-text> ...........................  15
      4.1.15. Processing of style Attribute ........................  15
      4.1.16. Internationalization Attribute Processing ............  15
      4.1.17. xmlns Attribute ......................................  15
      4.1.18. refer Attribute Processing ...........................  16
   4.2. Processor Allowances .......................................  16
      4.2.1. Processor Default Presentation ........................  16
      4.2.2. Processor Default Behaviors ...........................  16
      4.2.3. Processing Elaborations Over Native MML Definitions ...  17
5. MML Schema Header Documentation .................................  17
   5.1. MIME Type Usage and mime.xsd ...............................  17
   5.2. MML Header Documentation ...................................  18
      5.2.1. Root Element ..........................................  18

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      5.2.2. <session> Tag .........................................  18
      5.2.3. <address> Tag .........................................  19
      5.2.4. <to>, <copy>, <blind-copy>, and <from> Tags ...........  19
      5.2.5. <reply-to> Tag ........................................  19
      5.2.6. <attachments> Tag .....................................  19
      5.2.7. <collection> Tag ......................................  19
      5.2.8. <collection-name> Tag .................................  19
      5.2.9. <collection-file> Tag .................................  20
      5.2.10. <collection-type> Tag ................................  20
      5.2.11. <collection-description> Tag .........................  20
      5.2.12. <file> Tag ...........................................  20
      5.2.13. <file-name> Tag ......................................  20
      5.2.14. <file-type> Tag ......................................  20
      5.2.15. <file-description> Tag ...............................  20
      5.2.16. <subject> Tag ........................................  20
      5.2.17. <presentation> Tag ...................................  21
      5.2.18. <stylesheet> Tag .....................................  21
      5.2.19. <source> Tag .........................................  21
      5.2.20. <source-uri> Tag .....................................  21
      5.2.21. <source-type> Tag ....................................  21
      5.2.22. <plain-text> Tag .....................................  21
      5.2.23. <markup> Tag .........................................  22
   5.3. <markup> Organization of Types and Groups ..................  22
      5.3.1. <markup> Element Organization .........................  22
      5.3.2. <markup> Attribute Organization .......................  23
   5.4. <markup> Attributes ........................................  23
      5.4.1. id Attribute ..........................................  23
      5.4.2. title Attribute .......................................  24
      5.4.3. class Attribute .......................................  24
      5.4.4. role Attribute ........................................  24
      5.4.5. uri Attribute .........................................  24
      5.4.6. direction Attribute ...................................  24
      5.4.7. orientation Attribute .................................  25
      5.4.8. wrap Attribute ........................................  25
      5.4.9. section-language Attribute ............................  25
      5.4.10. span-column Attribute ................................  25
      5.4.11. span-row Attribute ...................................  25
      5.4.12. refer Attribute ......................................  25
      5.4.13. scope Attribute ......................................  25
      5.4.14. long-form Attribute ..................................  26
   5.5. <markup> Elements ..........................................  26
      5.5.1. <define-list> Tag .....................................  26
      5.5.2. <define-item> Tag .....................................  26
      5.5.3. <define-term> Tag .....................................  27
      5.5.4. <definition> Tag ......................................  27
      5.5.5. <navigation-list> Tag .................................  27
      5.5.6. <navigation-item> Tag .................................  27
      5.5.7. <navigation-object> Tag ...............................  27
      5.5.8. <navigation-text> Tag .................................  28
      5.5.9. <order-list> Tag ......................................  28
      5.5.10. <unorder-list> Tag ...................................  28

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      5.5.11. <list-item> Tag ......................................  29
      5.5.12. <form> Tag ...........................................  29
      5.5.13. <form-body> Tag ......................................  29
      5.5.14. <table> Tag ..........................................  29
      5.5.15. <head-row> Tag .......................................  29
      5.5.16. <table-row> Tag ......................................  30
      5.5.17. <head-cell> Tag ......................................  30
      5.5.18. <table-cell> Tag .....................................  30
      5.5.19. <section> Tag ........................................  30
      5.5.20. <block-code> Tag .....................................  31
      5.5.21. <block-quote> Tag ....................................  31
      5.5.22. <citation> Tag .......................................  31
      5.5.23. <heading> Tag ........................................  32
      5.5.24. <object> Tag .........................................  32
      5.5.25. <object-text> Tag ....................................  32
      5.5.26. <object-uri> Tag .....................................  32
      5.5.27. <object-type> Tag ....................................  32
      5.5.28. <paragraph> Tag ......................................  32
      5.5.29. <separator> Tag ......................................  33
      5.5.30. <short> Tag ..........................................  33
      5.5.31. <button> Tag .........................................  33
      5.5.32. <cite> Tag ...........................................  33
      5.5.33. <emphasis> Tag .......................................  33
      5.5.34. <identifier> Tag .....................................  34
      5.5.35. <quote> Tag ..........................................  34
      5.5.36. <format> Tag .........................................  34
      5.5.37. <strong> Tag .........................................  34
      5.5.38. <title> Tag ..........................................  34
6. Protocol Compatibility ..........................................  34
   6.1. Simple Mail Transfer Protocol (SMTP) .......................  35
   6.2. Post Office Protocol - Version 3 (POP3) ....................  35
   6.3. Internet Message Access Protocol - Version 4rev1 (IMAP) ....  35
   6.4. Requirements for Web Mail ..................................  36
7. Default mime.xsd ................................................  36
8. MML Schema ......................................................  56
9. References ......................................................  71
10. Acknowledgements ...............................................  75
11. Author's Address ...............................................  75

1. Introduction
   MML as a standard is both a language and a standard list of
   processing constraints upon that language.

1.1. Scope
   This document seeks to fully describe the specification and syntax
   rules of the actual language, the constraints upon processing that
   language, and the inclusion of other standards or technologies.





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1.2. Requirements
   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [34].

   If an implementation, feature, or constraint does not satisfy a
   requirement level of MUST, MUST NOT, or REQUIRED for its respective
   statement, clause, phrase, or section that implementation, feature,
   or constraint MUST be considered failed.  Under such a circumstance,
   known as conditional compliance, a MML document MUST NOT be
   transmitted.  The ideal MML document will satisfy conditional
   compliance, SHOULD and SHOULD NOT conditions, known as unconditional
   compliance.

1.3. Terminology
   This document will use several terms to describe various features or
   components.

   tag
      A tag is a code command enclosed in angle brackets such as,
      "<strong>".  Every tag exists as pairs of an opening tag and a
      closing tag.  All closing tags are identical to their opening
      counter-part except that are preceded by a forward slash
      character, such as "</strong>".

   element
      The word "element" is synonymous and used interchangeably with the
      term "tag".

   simple block
      A simple block is a tag that is capable of containing text and/or
      line-level tags, but is not capable of containing complex blocks.

   complex block
      A complex block is a tag that is capable of containing simple
      blocks or complex blocks, but is not capable of containing text.

   line-level tag
      Line-level tags are only capable of existing in simple blocks.
      Line-level tags cannot contain other tags.

   processor
      The term processor is to refer to any application that processes,
      interprets, or seeks to process a MML document.  The term
      processor MAY typically refer to email client applications, but is
      not limited to such.  The term "MML processor" is directly
      synonymous to the term "mail client" used by other related
      specifications.




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   accessibility
      Accessibility is the degree of ease from which any human is
      equally capable of receiving data intended for human consumption
      from the desired document or request.  Accessibility MAY refer to
      persons with a sensory disability, a motor disability, or software
      impairment.

   understandability
      Understandability is the degree of ability by which a technology
      can be learned and used by a person who has never seen or used the
      technology previously.  Understandability also refers to the
      lack of effort necessary for an experienced user to consume and
      process the technology.

   semantics
      Semantics refers to the degree of description provided by meta-
      data and syntax rules either statically or through nesting and
      hierarchal implementation thereof.  The objective of semantics is
      to provide the most expansive description of data intended for
      human consumption without that description interfering with
      understandability during reading or writing.

   structure
      Structure refers to the effectual organization of data only as a
      result of well organized meta-data containers into a rigid
      hierarchy.

   session
      In the context of MML the term session only refers to an instance
      of communication, which is defined by the <session></session>
      tags.

   URI
      The abbreviation of URI is short for Uniform Resource Identifier.
      A URI is the address of a resource on a network or networks as
      defined by RFC 3986, addressed by RFC 3305, and supplemented by
      RFC 2368.

2. Philosophy of Design
   The philosophy of design represents a shell container of decisions
   whose intent is certain beneficial objectives and to identify
   negative consequences.  The design philosophies for MML creation are
   listed in order of most significant to less relevant.

2.1. Structure
   Structure is the primary design consideration influencing MML.  It is
   important that structure be the most important factor in the design
   of the language as all other design considerations are merely a
   result of the logic and conventions imposed by a well structured
   form.


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   The primary difference between MML and other markup languages is that
   proper structure is mandatorily imposed upon a document author.  This
   rigid inflexibility produces several profoundly significant benefits
   that exist inherently, which would otherwise merely be referred as
   best use.  The cost that comes from such rigidness is the inability
   to put content absolutely anywhere in a document to circumvent any
   potential processing flaws of a processing software.

2.2. Syntax Simplicity and Understandability
   Syntax in MML MUST be well-formed XML that conforms to the MML
   schema.  Every tag in MML MUST exist as a pair of opening and closing
   tags.  Syntax in MML is simple and always uniform.

   Tag names are English words and not abbreviations or shortcuts.  This
   is critical to understandability.  An abbreviation is a symbolic
   representation of its expanded value.  Although it may be faster to
   write <p> instead of <paragraph> we are saving time and physical
   effort only at the expense of increase mental effort.  If we know a
   <p> tag represents a paragraph then it becomes of a symbol of the
   word paragraph, which is a step of mental deduction.

   As humans we are rather so consumed by symbolic use that it seems a
   trivial effort to back out a single step of symbolic deduction.  The
   savings become significantly more noticeable given the quantity of
   which meta-data often occurs in large mark up documents.  The end
   result is that it is lesser mentally exhausting to read a document
   with descriptive and simple meta-data using complete words.

2.3. Semantics
   Semantics are necessary for binding data, which is useful only to
   humans, and processing syntax, which is only useful to language
   processors.  The objectives of semantic processing is for semantic
   processors to parse human supplied data and make decisions upon data
   that result in output relative to human decisions.
   
   MML was designed with consideration for applying semantics in the
   least specific manner.  Tag names were created for understandability
   and not semantics.  Any benefit received to semantics is purely
   consequential.  There are two remedies to this intended lack of
   elaboration.  Every tag in the <markup> section of MML is granted use
   of the role attribute.  For the role attribute please see section
   5.4.4. role Attribute.  Hierarchal semantics are the primary
   unintended beneficiary of a rigid structure imposed upon the data.
   A combined use of the role attribute or the tag names and the
   hierarchal structure in which they exist is the second remedy for the
   lack of semantic elaboration.






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   Even though conventions in MML were not created to directly benefit
   semantics the conventions of semantic languages, such as Resource
   Document Framework, were the primary influencing factor in creating
   the concepts and rules for imposing structure and tag hierarchy.

2.4. Accessibility
   It is an important factor that all persons are equally capable of
   accessing, using, and understanding documents defined as MML.
   Accessibility is a lesser important design factor as many concerns of
   accessibility are addressed by proper use of semantics,
   understandability, and usability.  Usability is primarily a result of
   interaction of the data, which exceeds the scope of this document.

   There are constraints upon processing specified by this document that
   may serve to benefit accessibility.  See section 4.1. Processor
   Requirements and Constraints.

2.5. Presentation
   Presentation is perhaps the least concern of all design factors
   influencing MML.  All presentation will exist in either an external
   stylesheet(s) or the default presentational conventions supplied by
   the MML processor.

   This version of MML only recognizes Cascading Style Sheets and
   Extensible Stylesheet Language as presentation languages.  The
   degree of processing compliance afforded to those languages and
   which versions are process-able are processor specific concerns,
   which exceed the scope of this document.  Please see section
   3.4. Stylesheet Technologies for more information.
   
   MML processors SHOULD make no assumption that there is an implied
   default presentation that any tag, element, or concept must adhere
   to.  Please see section 4.2.1. Default Presentation.

2.6. Security
   While security is always important it is of trivial concern to the
   describing of data, which is why security is a consideration for the
   design of MML, but is lowest priority.  Much of the effort in
   assuring MML data remains confidential and maintains integrity rests
   on the processing of the MML processor, the security of the protocols
   used to transport the data, and the general security practices of
   document authors.

   Nonrepudiation is the most important security consideration, except
   perhaps for encryption, concerning email.  The job of nonrepudiation
   rests most prominently with proper storage practices of documents by
   users and time/date stamps imposed by email processors on the arrival
   of mail documents.  MML does contribute to nonrepudiation by
   requiring a timestamp in a manner beyond user control.  Please see
   section 4.1.4. Session Time-stamp and 5.2.2. <session> Tag.


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   MML does provide a method for specifying implementation of public key
   distribution to facilitate encryption.  Please see section 3.6.
   Public Key Infrastructure.

   MML also implements a description scheme for every attached asset
   using MIME to identify various types of media.  Media can only be
   executed according to the specified MIME type value.  The intent is
   that a file that looks like a graphic and has the file extension of a
   a graphic may actually be a malicious executable program, but if it
   has a specified MIME type of a graphic format it can only open as a
   graphic or it MUST NOT be processed.  For more information please see
   section 3.8. Multipurpose Internet Mail Extensions and section 4.1.3.
   MIME Execution Restriction.

3. External Technologies
   In order to advance the functionality of this technology it is
   necessary to incorporate use of prior existing standards.

3.1. Extensible Markup Language (XML) and W3C XML Schema
   MML is written in W3C XML Schema, which is written XML.  As a result
   MML code is case sensitive.  This means all tag names MUST be lower
   case.  XML also requires that all attribute values MUST be quoted,
   tags MUST be properly nested, and every opening tag MUST have a
   corresponding closing tag.  Failure to adhere to these syntax rules
   will result in the document not validating, which will cause it to
   not send.  Please see section 4.1.1. Validation for more information.

3.2. XForms 1.1
   XForms is the only form method specified in MML.  Where XForms usage
   is allowed by the MML schema it MUST be used in accordance with the
   XForms schema: http://www.w3.org/Markup/Forms/2002/XForms-Schema.xsd
   Processors MUST use XForms version 1.1 to be compliant with this
   version of MML.

3.3. Accessible Rich Internet Applications
   The standards specification Accessible Rich Internet Applications,
   WAI-ARIA, is not included into this version of MML due to the
   specification not being formalized at the time of this writing.
   WAI-ARIA is intended to be implemented in future versions of MML.
   For more information please see: http://www.w3c.org/WAI/

3.4. Resource Document Framework
   Resource Document Framework, RDF, is not an included technology of
   this specification, however RDF did significantly influence design
   patterns of MML.  RDF implementation MAY occur as a server-side
   feature, an optional client specific feature, or a MML processor
   behavior feature.  RDF implementation MUST NOT interfere with
   conventions, syntax, data, or meta-data supplied in the document
   directly.  This is necessary so that a MML document maintains a



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   pre-RDF existence for distribution to other users that may not be
   capable of processing RDF.  For more information please see:
   http://www.w3c.org/RDF/

3.5. Stylesheet Technologies
   This version of MML recognizes only Cascading Style Sheets (CSS) and
   Extensible Stylesheets Language (XSL) as stylesheet languages.  MML
   imposes no requirement to support stylesheets.  If a MML processor
   does attempt to support a particular stylesheet it SHOULD state what
   version is supported and SHOULD fully support that version according
   to its specification.  For more information on CSS please see
   http://www.w3.org/Style/CSS/  For more information on XSL please see
   http://www.w3.org/Style/XSL/

3.6. Behaviors and Scripting
   MML does not support any scripting or behavior technologies.  This
   version of MML does not provide a solution to likely cross-site
   scripting vulnerabilities, breaches of non-repudiation, or
   interference to the integrity of the data that may result from the
   execution of scripting at the user agent software.  Standards and
   technologies that wish to dynamically alter or access a MML document
   SHOULD do so only using XPath or DOM expressions and MUST NOT violate
   the document segragation imposed by processing the <session> element.

3.7. Public Key Infrastructure
   MML supports the transfer of public keys by directly embedding the
   hash value of the public key into the document.  MML provides no
   support for specifications regarding encryption, data transport, or
   confidentiality.  These are application specific and protocol
   features that exceed the scope of this document.  Please see section
   5.2.8. <public-key> tag for more information on MML implementation.
   For PKI specifications please see: http://www.rsa.com/rsalabs/pkcs/

3.8  Uniform Resource Identifier
   Uniform Resource Identifier (URI) is a representation of an address
   to an external asset.  MML requires the use of URIs to specify
   locations of any object or stylesheet.  Aside from text the only data
   that MAY be included directly into the document are public key
   hashes.  For additional information please refer to RFC 3305.

3.9. Multipurpose Internet Mail Extensions
   Multipurpose Internet Mail Extensions (MIME) is specification
   designed to support an expanded character set beyond the basic 7-bit
   ASCII natively supported by SMTP.  For more information on the MIME
   specification please refer to RFC 2045, RFC 2046, RFC 2047, RFC 4288,
   RFC 4289, and RFC 2077.

4. Processor Roles
   The role of a processor of MML is to conform to the following
   specified requirements.  Processors of MML are, however, allowed
   certain freedoms from presumption that are also specified.

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   MML processors are encouraged to test the limits of innovation.
   Diversity, usability, and customization are necessary results of
   competition.  The intent of section 4.1. Processor Requirements and
   Constraints is to impose requirements upon MML processors to ensure
   the integrity of the language.  The intent of section 4.2. Processor
   Allowances is to illustrate some areas where MML processor vendors
   are free to explore without fear of violating this specification.

4.1. Processor Requirements and Constraints
   The intent of imposing requirements and constraints unto the
   processor is to provide a uniform existence for data, meta-data, and
   syntax rules contained in a MML document not at the burden of a
   document author.

4.1.1. Validation
   It is absolutely essential that a MML document MUST validate against
   the MML schema prior to transmission.  If a MML document does not
   validate it MUST NOT be transmitted as email across any email
   specific protocol or Hyper Text Transfer Protocol.  A MML processor
   is not REQUIRED to process any malformed or invalid MML document.

   It is not invalid, according to some schema validators, for a session
   author to include empty tags, also known as nil content, such as
   <style></style>.  It is, however, invalid to include nil content
   elements, in accordance with the XML Schema standard, without
   explicitly stating the XSI:nil="true" attribute.  Empty tags MUST
   be removed by the MML processor during validation.  Every tag SHOULD
   contain text, other tags, or both if so allowed.

4.1.2. RFC 2822/5322 Conformance
   A MML processor MUST create RFC 5322 conformant mail headers for
   backwards compatibility.  MML aware clients/servers MUST remove this
   header data and instead rely only upon the header information
   specified within the MML code.  This is necessary to ensure seamless
   transactions across the SMTP protocol to clients not prepared to
   receive MML.  This header data MUST be created after document
   validation for transport and prior to the document being transported.

4.1.3. Session Separation and Presentation
   MML processors MUST process each session of a MML document
   separately.  This means a stylesheet specified in one particular
   session MUST NOT be processed in another session on the same
   document.  For instance a background specified, via stylesheet, in
   one session cannot exist as a background in any other session unless
   so specified in each other session even if in the same document.

   A MML processor SHOULD allow session authors to alter the
   presentation of all elements and content in a session even if those
   elements or content exist outside the message body.  This is not a
   requirement because MML processors MAY choose to display the session
   header information only in their application shell opposed to text.

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4.1.4. Session Preservation
   All prior sessions received in a MML document MUST be preserved
   verbatim, including whitespace and presentation.  Decisions upon
   prior sessions MUST NOT be allowed except whether external assets MAY
   be processed.  A MML processor SHOULD take steps to prevent prior
   sessions from manual alteration by a session author.

4.1.5. Character Set
   The character set for this version of MML MUST be UTF-16BE.

4.1.6. Session Time-stamp
   The value of the time-stamp attribute MUST be written by the MML
   processor between the moment the session author submits the document
   for transmission and the validation by the MML processor.  The MML
   processor MUST write over any value supplied by the author with the
   correct value.  The value MUST be based upon the local system clock.

4.1.7. URI Resolution
   MML processors MUST set a standard timeout for any URI that is
   referenced in a MML document.  The length of that timeout MAY be
   determined by the MML processor.  User adjustment to the timeout
   length setting of the MML processor is OPTIONAL.  If a MML processor
   cannot resolve any resource at its specified URI timeout that
   resource MUST fail.

4.1.8. MIME Execution Restriction
   Every object, stylesheet, or other external resource MUST be
   processed strictly according to its specified MIME type.  If a
   resource does not match its associated MIME type it MUST NOT be
   executed.  Processing of any external resource to a MML document by a
   MML processor is OPTIONAL.

4.1.9. Caching
   External assets, such as stylesheets or objects, MUST be cacheable by
   the MML processor.  Caching significantly improves performance by
   reducing the demand for bandwidth and allowing access to content even
   when offline.  Options, configuration, and implementation MUST exist
   entirely at the discretion of the MML processor.

4.1.10. Local Processing
   MML processors MUST locally contain all required code components
   necessary to process and validate a MML document according to the
   MML schema.  These components can be obtained from the following
   list:

   * http://mailmarkup.org/mail.xsd
   * http://www.w3.org/MarkUp/Forms/2002/XForms-Schema.xsd
   * http://www.w3.org/MarkUp/SCHEMA/xml-events-attribs-1.xsd
   * http://www.w3.org/2001/XMLSchema.xsd
   * http://www.w3.org/2001/03/xml.xsd

   
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   * http://www.w3.org/2001/XMLSchema.dtd
   * http://www.w3.org/2001/datatypes.dtd
   * http://mailmarkup.org/mime.xsd

   MML processors MUST NOT require the use of a network or internet
   connection to process or validate a MML document.

4.1.11. MIME Catalogue
   A MML processor's list of acceptable MIME types MUST exist as a local
   schema file.  This file MUST be available for editing by either an
   administrator or common user.  Adding new MIME types to the list will
   likely result in a failure to process outside an internal network.
   Removing MIME types from the list MUST result in a failure to process
   media of those types.  By default the values in the MIME catalogue
   file will be every IANA registered type.

4.1.12. From and Reply-to Tags
   The <from> and <reply-to> tags are REQUIRED tags, so the tags will
   exist even if their content is null.  If their content is null the
   MML processor MUST supply default values of the session author's
   email address.  This MML processor supplied default content MUST be
   supplied by the MML processor between the moment the session author
   submits the document for transmission and the REQUIRED validation by
   the MML processor.  The default value for the <from> tag MUST be the
   address represented by the author.  The default value for the
   <reply-to> tag MUST match the default value of the <from> tag.

   Session authors are allowed to specify content for these elements to
   hide their email address.  The benefit is to customize how other
   session authors can control direct traffic, such as reply and forward
   traffic, back to their email address.  It is important to understand
   the actual traffic benefit of these fields as they offer absolutely
   no security advantage.  MML processors MUST NOT use, process, or
   regulate the <from> or <reply-to> tags for any intent related to
   security.  Email transmission protocols operate in unencrypted
   plain-text by default, which is where any user can easily find any
   address or identity information.

   Please see section 5.2.4. <to>, <copy>,  blind-Copy>, and <from> Tags
   and section 5.2.9. <reply-to>.

4.1.13. Attachments
   Attachments to the current session MUST be sent with the actual MML
   document.  Attachment persistence is OPTIONAL to the MML processor
   vendor.  Attachment persistence refers to whether or not attachments
   will continue to be sent with the MML document after the document
   session arrives at its originally intended destination(s).  A MML
   processor SHOULD allow users to choose to allow persistence.

   Attachments MUST be processed only according to their specified type.
   Processing of attachments by the MML processor is OPTIONAL.  The type
   
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   specified for <collection-type> MUST represent every file in that
   respective <collection>.  If the <collection-type> tag is not present
   the files located in the collection MUST NOT be executable from the
   MML processor, MML document, or any other mail service software.

4.1.14. Processing of <plain-text>
   Content provided in <plain-text> MUST be processed as plain text
   characters and/or whitespace only.  Code MUST NOT be processed,
   rendered, or transformed in this tag.  XML reserved syntax characters
   MUST be properly escaped automatically by the MML processor or
   validation SHOULD expect to fail.

4.1.15. Processing of style Attribute
   The value supplied by the style attribute is defined in the MML
   schema as lowercase alpha characters, uppercase alpha characters,
   and/or numbers plus a colon character (:) plus lowercase alpha
   characters, uppercase alpha characters, and/or numbers.  The
   characters supplied prior to the colon MUST represent the value
   supplied in a <stylesheet-namespace> element of the same session.
   The value supplied after the colon SHOULD represent a reusable
   processing declaration defined inside the stylesheet, such as a CSS
   class.  An example of a supplied value: "namespaceName:CSSclass09".

   Stylesheet processing is OPTIONAL.  If the noted stylesheet cannot be
   resolved or if the value supplied by the style attribute is either
   malformed or fails to match a stylesheet of the same session this
   attribute MUST NOT be processed.

4.1.16. Internationalization Attribute Processing
   Text MUST be processed in accordance with the defined values for the
   four internationalization attributes.  For processing descriptions
   please refer to these sections:
      * section 5.4.6. direction Attribute
      * section 5.4.7. orientation Attribute
      * section 5.4.8. wrap Attribute
      * section 5.4.9. section-language Attribute

   Failure to process internationalization attributes according to
   their definition MUST result in conditional compliance failure.

4.1.17. xmlns Attribute
   The xmlns attribute is not defined in this specification.  It is
   defined in the specification for Namespaces in XML 1.0.  It is
   considered an included technology by virtue of the xml.xsd schema
   that is imported into the XMLSchema.xsd schema that is imported into
   the mail.xsd that defines MML.  Use of the xmlns attribute MUST be
   allowed on the <session> element and any element contained by the
   <session> element in accordance with XML processing guidance defined
   by XML and Namespace standards.



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4.1.18. refer Attribute Processing
   The refer attribute MUST NOT be allowed to reference id values
   outside the specific <markup> element containing the refer attribute.
   For more information see 5.4.12 refer Attribute.

4.2. Processor Allowances
   This document does not exist to define the role of MML processors for
   features that exceed the scope of this document.  This section only
   serves to dispel assumptions and specify certain freedoms allowed to
   MML processors, which are not be allowed to processors of other
   markup languages.

4.2.1. Default Presentation
   This specification does not make any statements regarding
   presentation of the language.  This means a MML processor is free to
   determine the default presentation for tags and objects.  This
   default presentation MAY apply to any or all parts of a MML document.
   This means that presentation provided from a MML processor fits a
   wider scope than presentation specified by a MML author since any MML
   author can only specify presentation by use of an external stylesheet
   and stylesheet processing is limited to its session of the document.

   MML processor default presentation MUST be lower priority than
   presentation defined in a stylesheet.  If a conflict in presentation
   arises between the default and a stylesheet the presentation
   specified by the stylesheet MUST dominate even in regards to
   cascading.  This means a MML processor determines font size, color,
   font, and so on until so specified by a stylesheet.  A MML processor
   determines, by default, whether complex and simple blocks impose a
   line break, wrap, float, or so on.

   A MML processor SHOULD allow a user to customize or alter its
   default presentation.  This specification will not mandate
   customization, however, accessibility concerns SHOULD be considered
   for changing text size, turning off stylesheets, and replacing
   objects with their respective text content.

4.2.2. Default Behaviors
   This specification states no directive for behaviors or controls
   upon the data or the usability thereof.  There is no convention for
   allowing client-side scripting in MML and any scripting that does
   exist MUST be processed as plain text content.  MML processors SHOULD
   allow behaviors that increase accessibility more importantly than
   usability.

   Section 3.3. Resource Document Framework states that RDF is not an
   included technology in this specification and MUST NOT interfere
   with conventions, syntax, data, or meta-data supplied in the document




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   directly.  What it does not say is that semantic technologies MAY be
   used to auto-fill many areas of MML based upon a user's data habits.
   Semantic technologies MAY also be used for searching, data sorting,
   or other processing features to the data defined by the MML document.
   Those semantic technologies MUST NOT, however, alter the contents of
   the MML document.

4.2.3. Processing Elaborations Over Native MML Definitions
   MML processors MUST be capable of processing the full MML
   specification.  MML processors MAY allow processing of or definition
   of elements or conventions not defined by this MML specification.
   Such elaborations MUST NOT interfere, limit, constrain, remove, or
   disable any aspect of the MML specification.  Any elaboration,
   element, or convention not defined by this MML specification is
   OPTIONAL of MML processors.

5. MML Schema Documentation
   This section is intended to provide a description of the language
   along with justifications for certain conventions used.  This section
   is informational only.  All processing declarations are stated in
   section 4. Processor Roles and section 5. MML Schema.

   If an element is followed by "0" it MAY occur 0 or 1 time.  If an
   element is followed by "+" it MUST occur once, but it MAY occur more
   than once.  If an item is followed by "0+" it MAY occur 0 or more
   times.  If an element does not have these descriptors it MUST occur
   once and only once.  Attributes MAY be followed by "0", which
   indicates the attribute in concern is optional.  Attributes MUST NOT
   occur more than once in any element.

   Those elements noted as (XForms) are defined by the XForms
   specification and not this document.  For more information see
   section 3.2. XForms and 4.1.8. Local Processing.  These elements MUST
   be processed in strict accordance with the XForms schema.

5.1. MIME Type Usage and mime.xsd
   MIME types MUST be stored in the mime.xsd document, which is merely a
   catalogue of all IANA registered MIME types at the time of this
   writing.  The information stored in mime.xsd is used in the MML
   schema through the use of the "mime-type" schema complex type.

   Elements based upon the "mime-type" element type are allowed only one
   of nine possible child elements.  These child elements each represent
   a IANA registered content type.  The values for those child elements
   MUST be a MIME sub-type that exists in the local mime.xsd file.  The
   child elements are:
      * <application> or <audio> or <example> or <image> or <message> or
        <model> or <multipart> or <text> or <video>




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5.2. MML Header Documentation
   The code described in this section exists in MML documents without
   regard to how the message is formatted.  For more information about
   the message body see section 5.2.2. <session> Tag and section 5.3.
   <markup> Element Documentation.

5.2.1. Root Element
   The root element of MML is the tag <mail>.  The root tag is only
   capable of containing <session> elements.  This tag MUST contain the
   following attributes:
      * mail-type="application/mail+xml"
      * version="1.0"
      * xmlns:xfm="http://www.w3.org/2002/xforms"
      * xmlns:xs="http://www.w3.org/2001/XMLSchema"

5.2.2. <session> Tag
   The session tag contains all information to represent an instance of
   communication including markup and header information.  A session
   tag's child tags are as follows:
      * <xsd:import> 0+
      * <xsd:include> 0+
      * <address>
      * <attachments> 0
      * <subject>
      * <presentation> 0
      * <source> or <markup> or <plain-text>

   The <session> tag's attributes:
      * time-stamp
      * language (optional)

   The session tag allows three methods of communicating the message
   body.  The source method allows a session author to send an external
   resource as the message body.  Please see section 5.2.26 <source>
   Tag.  The plain-text method allows a session author to communicate
   using only text characters and whitespace.  Please see section
   5.2.29. <plain-text> Tag.  The markup method allows a section author
   to use MML markup to describe the data.  Please see section 5.2.30.
   <markup> Tag and section 5.3. <markup> Organization of Types and
   Groups and 5.4. <markup> Attributes and 5.5. <markup> Elements.

   The time-stamp attribute is described in section 4.1.6. Session
   Time-stamp.  The optional language attribute allows a session author
   to describe the majority language of the session using values
   appropriate to the XML Schema language data type.  The default value
   is "en" if none is specified.  Mail client software SHOULD allow a
   user to specify a default value for the language attribute.





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5.2.3. <address> Tag
   The address tag is a high level tag designed to store child tags
   containing email address information.  The child tags are:
      * <to> +
      * <copy> 0+
      * <blind-copy> 0+
      * <reply-to>
      * <from>

5.2.4. <to>, <copy>, <blind-Copy>, and <from> Tags
   These tags are identical in their syntax.  They store only the value
   of a properly formed email address.  They may contain the optional
   attributes of alias and public-key.  The alias is intended to contain
   a value more human readable representation of an email address, such
   as a person's name.  The public-key attribute is intended to store
   text characters that represent a hash function name and a hashed
   public-key for asymmetric encryption.  These two values MUST be
   separated by a colon only with the hashed key value after the colon.
   The hash function name MUST be uppercase alpha or numbers only.

   The <to>, <copy>, <blind-Copy>, and <from> tag's attributes:
      * alias (optional)
	  * public-key (optional)

5.2.5. <reply-to> Tag
   The <reply-to> tag is identical to the <from> tag except that it may
   contain either a valid email address or a value of no-reply.  This
   tag is used to set an address for deflecting email replys from the
   address  used to send the email or to establish an alternate
   destination for receiving replies.

5.2.6. <attachments> Tag
   The <attachments> tag is a high level tag for specifying file(s) for
   transfer with the document.  Attached files are not intended for
   processing in the message body.  This tag has two children which may
   occur as many times as needed.  At a minimum only one of these child
   elements MUST occur:
      * <collection> + and/or <file> +

5.2.7 <collection> Tag
   The <collection> tag is intended to serve as a collection of multiple
   files of the same specified type.  This tag has four child tags:
      * <collection-name>
      * <collection-file> +
      * <collection-type> 0
      * <collection-description>

5.2.8. <collection-name> Tag
   <collection-name> tag is a REQUIRED child of <collection>.  This may
   be any string value on a single line.  The intent of this tag is to
   provide a simple name or label for the attached collection.

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5.2.9. <collection-file> Tag
   <collection-file> tag stores the file name of a particular file in a
   collection.  This tag MUST exist for each file that is to exist in
   the collection.

5.2.10. <collection-type> Tag
   The <collection-type> tag is a "mime-type" complex-type tag as
   specified in mime.xsd.  The value provided for this tag MUST
   represent every file in the collection.  This tag is OPTIONAL.  If
   this tag is not present the files present in the collection MUST NOT
   be processed by the MML processor.  See section 4.1.11. Attachments
   for information on processing requirements.  Please see section 5.1.
   MIME Type Usage and mime.xsd for information about the specified type
   "mime-type".  MML processors are not REQUIRED to process attached
   collections.

5.2.11. <collection-description> Tag
   This tag exists to specify a text description of the collection.
   The content for this tag MAY represent examples of intended use,
   explanations, file ownership, origin information, and so forth.

5.2.12. <file> Tag
   The <file> tag is intended to serve as a single attached file.  This
   tag has three child tags:
      * <file-name>
      * <file-type>
      * <file-description>

5.2.13. <file-name> Tag
   <file-name> tag is a REQUIRED child of <file>.  The value for this
   tag MUST be a non-colonized name.  This tag represents the name of
   the file being attached.

5.2.14. <file-type> Tag
   This tag is of type "mime-type".  The attached file MUST be processed
   according to the value supplied in this tag, or it MUST NOT be
   processed by a MML processor.  Processing of attached files by MML
   processors is OPTIONAL.

5.2.15. <file-description> Tag
   This tag allows a session author to enter any normalized string value
   that describes the attached file.  This tag is REQUIRED.

5.2.16. <subject> Tag
   The <subject> tag value id a normalized string.  This REQUIRED tag
   sets the subject of the document session.  This tag is equivalent to
   the subject of traditional email.





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5.2.17. <presentation> Tag
   All presentation, aside from MML default presentation, is set for a
   session in this high level tag.  This tag is nothing more than a
   container for its one child element that may occur more than once.
      * <stylesheet> +

5.2.18. <stylesheet> Tag
   Each <stylesheet> tag represents a single stylesheet reference.  This
   tag MUST have a URI of valid syntax as its value.  The optional media
   attribute identifies the output media the stylesheet is attempting to
   supply presentation for, which defaults to a value of "screen".
   Required attribute style-namespace is a unique value that will serve
   as named prefix for stylesheet declarations from this stylesheet. 
   The value for style-namespace MUST follow the same syntax and
   processing requirements as the attribute id.  This attribute value
   MUST be unique within the scope of the <session> and SHALL NOT be
   unique in the entirety of a MML document.  The prefix is REQUIRED for
   stylesheet references using the "style" attribute that is available
   to elements in the <markup> section of the session.  See section
   5.4.3. style Attribute for more information.  The REQUIRED attribute,
   "style-type", accepts only one of three values:
      * application/xslt+xml
      * text/css

5.2.19. <source> Tag
   The <source> tag is one of three methods of creating the message
   body.  The intent of this tag is to allow an external resource to act
   as the message body.  There is no requirement for a MML processor to
   process any external resource, so the content established by the
   <source> tag SHALL NOT always be communicated.  This tag has two
   REQUIRED children:
      * <source-uri>
      * <source-type>

5.2.20. <source-uri> Tag
   This tag MUST only contain a URI of the requested resource that is to
   act as the body of the session.

5.2.21. <source-type> Tag
   This tag is of element type "mime-type".  The type determines how or
   if the external resource described in <source-uri> MUST be processed
   by the document's destination.

5.2.22. <plain-text> Tag
   This tag is the second of the three methods for communicating the
   body of the session.  This tag MUST contain only plain text.  Code
   MUST NOT be processed in this tag.  The intent of this tag is to
   allow session authors to communicate using text without interference
   to the processing of that content.  Presentation MAY be applied to
   <plain-text> content if the MML processor so allows and a stylesheet
   is provided.

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5.2.23. <markup> Tag
   This tag allows the use of MML to describe and organize content.
   This is the advised method of communicating content in MML.  See
   section 5.3. <markup> Element Documentation for more information.

5.3. <markup> Organization of Types and Groups
   This section is intended to providing descriptive documentation for
   the part of the language dedicated to describing information that is
   intended to be read by an email recipient as a message body.

5.3.1. <markup> Element Organization
   The elements in this section of MML are arranged in three groups:
   complex-blocks, simple-blocks, and inline elements.

   A complex-block is a tag that is capable of containing of either
   simple-blocks or simple-blocks plus other complex-blocks.  Complex-
   blocks are not capable of containing text content or inline elements.
   These following tags are the high level complex-blocks:
      * <define-list>
      * <navigation-list>
      * <order-list>
      * <unorder-list>
      * <table>
      * <section>
      * <form>

   A simple-block is a tag that is capable of containing text and inline
   elements, but is not capable of containing other simple-blocks or
   complex-blocks.
      * <block-code>
      * <block-quote>
      * <citation>
      * <heading>
      * <object>
      * <paragraph>
      * <separator>

   Inline elements are not structural elements.  These elements MUST
   exist in a simple-block container.  Inline elements are intended to
   describe text content, supply additional meta-data, or apply more
   specific presentation.
      * form controls (XForms)
      * <short>
      * <button>
      * <cite>
      * <emphasis>
      * <identifier>
      * <quote>
      * <format>
      * <strong>
      * <title>

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5.3.2. <markup> Attribute Organization
   The attributes in the <markup> section of MML are arranged in the
   following attribute groups: "core attributes", "core attributes plus
   uri", "internationalization attributes", and "cell attributes".
   The "core attributes" are applied to nearly every element in the
   markup section.  This attribute group is always optional.  The group
   contains the following attributes:
      * id
      * title
      * style
      * role

   The "core attributes plus uri" group is literally the "core
   attributes" group with the added uri attribute.  It was necessary to
   specify these two groups separately because many elements require a
   URI and many MUST NOT receive a URI.  These attributes are in the
   "core attributes plus uri" group:
      * id
      * title
      * style
      * role
      * uri

   The "internationalization attributes" exist only to alter the order
   in which text is rendered.  This is not a presentation issue of
   altering how text appears, but how it functionally contributes to
   processing dependencies to the computer for the benefit of assistive
   technologies.  MML processors SHOULD allow users to determine the
   default rendering methods of text.
      * direction
      * orientation
      * wrap
      * section-language

   The "cell attributes" group is a set of attributes specific to table
   cell elements.  These attributes include the following:
      * span-column
      * span-row

5.4. <markup> Attributes
   This section is a per attribute list of attributes used by variou 
   tags in the <markup> section of a MML document.

5.4.1. id Attribute
   This attribute exists to assign a unique identification to an
   element.  The value for this attribute MUST NOT contain punctuation,
   white space, or XML syntax characters.  The value MUST allow Unicode
   word characters in accordance with the XML regular expression
   definition for a word character.  This attribute is intended to
   create a unique hook to a particular element for MML processor
   specific behavior or presentation.  There are some elements that

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   exist as a pair set and require the id attribute to refer to each
   other.  The id attribute MUST be unique per <session> section and
   SHALL NOT be unique per a MML document of multiple sessions.

5.4.2. title Attribute
   The title attribute is intended to supply additional content to an
   element beyond its contained text.  The value for this attribute MUST
   be whitespace normalized text.  This attribute is supplied for the
   semantic and accessibility benefits of expanded meta-data for human
   consumption.

5.4.3. style Attribute
   This attribute exists to reference a reusable stylesheet property.
   The value for this attribute MUST be a set of Unicode word characters
   in accordance with the XML regular expression definition of a word
   character plus a colon followed by a series of Unicode word
   characters.  The value before the colon MUST represent the value of
   any supplied stylesheet-namespace attribute.  This tells the MML
   processor which stylesheet the style reference is referring to.  The
   value after the colon MUST represent some designation defined in the
   stylesheet, such as a CSS class name.  An example is:
   "namespace:CSSclass09".

5.4.4. role Attribute
   This attribute is intended to allow for specific semantic
   redefinition of any element where its use is allowed.  If a session
   author had the ability to rename a tag to something more semantically
   specific that new name is the value that SHOULD fill the role
   attribute.  The value of the role attribute SHOULD NOT challenge or
   contradict the intent of the named element it is used with.

   This attribute is expected to offer significantly expanded utility in
   future versions of MML.  The WAI-ARIA technology and RDF derived
   technologies are expected to benefit from use of the role attribute.

5.4.5. uri Attribute
   This attribute MUST contain only a URI value as defined by RFC 3986
   or RFC 2368 for email addresses specifically.  Use of this attribute
   is equivalent to imposing a webpage hyperlink.  A same-document
   referrence, referred to as a URI fragment, MUST refer only to the
   value of a specified id attribute value within the same session.

5.4.6. direction Attribute
   The direction Attribute determines which direction the text is to
   flow as it is typed.  The default value is left to right if
   orientation has a value of horizontal or top to bottom if
   orientation has a value of vertical.  The acceptable values are "tl",
   which indicates starting from the top or left, or "br", which
   indicates starting from the bottom or right.



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5.4.7. orientation Attribute
   This attribute determines whether text characters render in a
   vertical or horizontal manner.  The acceptable values are
   "horizontal" or "vertical".  Horizontal is the default value.

5.4.8. wrap Attribute
   This attribute determines how lines of text are rendered to the page.
   The acceptable values for this attribute are "standard", "reverse",
   or "none".  A value of "standard" does nothing different and is the
   default value.  The value "reverse" MUST force text render opposite
   of its standard behavior.

   Assuming direction and orientation are at default standard behavior
   is to wrap a line of text below the prior existing text.  Under those
   conditions a value of "reverse" MUST force the line of text to wrap
   above the prior existing line of text.

   A value of "none" forces the text to not wrap.  Under the condition
   that non-wrapping text is wider or taller than its container the
   container MUST stretch and the page MUST scroll to keep the text
   visibly legible so long as there are not presentation specifications
   to the contrary.

5.4.9. section-language Attribute
   The attribute section-language specifies the language of a particular
   section, container, or element in the <markup> section.  This is
   absolutely necessary to alert readers and semantic devices that the
   natural language has changed from the default specified language.
   The values for this attribute MUST be ISO 639 language codes.

5.4.10. span-column Attribute
   This attribute allows a <table-cell> or <head-cell> to occupy more
   than one column in a table.  The values for this attribute MUST be a
   positive integer.  The default value is "1".

5.4.11. span-row Attribute
   The attribute span-row allows a <table-cell> or <head-cell> to occupy
   more than one row in a table.  The values for this attribute MUST be
   a positive integer.  The default value is "1".

5.4.12. refer Attribute
   This attribute is a reference to the value of an id attribute
   supplied on another element of the same <markup> section.  If the
   value of this attribute does not match an existent id attribute value
   of only the same session the document MUST NOT validate.

5.4.13. scope Attribute
   This attribute is used in table header cells to determine which table
   cells the header is providing a heading for.  The values for this
   attribute MUST be: column, row, group-column, or group-row.


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   The value "column" dictates that a header cell is providing a heading
   for only the first column of cells the header cell occupies.  The
   value "row" dictates that a header cell is providing a heading for
   only the first row of cells the header cell occupies.  A value of
   "group-column" dictates that a header cell provides a heading for all
   cells in all columns that it occupies.  The value "group-row"
   dictates the header cell is providing a heading for all cells in all
   rows it occupies.

   The word first, as used in defining column and row as values to the
   scope attribute, MUST refer to the first group of elements as
   dictated by the rendering direction of text set using
   internationalization attributes.

5.4.14. long-form Attribute
   This attribute MUST serve to represent the expanded text that is
   described by the <short> element.  An example is: <short
   long-form="Mail Markup Language">MML</short>.

5.5. <markup> Elements
   This section is a per element list of all elements that MAY exist in
   the <markup> section of a MML document.

5.5.1. <define-list> Tag
   This element is intended to establish a list of definitions by
   matching any number of defining terms to any number of definitions.
   This element contains only one child element, but that element may be
   used more than once.
   Child:
      * <define-item> +

   Attributes:
      * core attributes 0

5.5.2. <define-item> Tag
   The <define-item> tag represents a single defining instance.
   The associations drawn by the child tags are as follows: multiple
   defining terms mapped to a single definition, a single term mapped
   against multiple definitions, or multiple terms that commonly share
   multiple definitions.  As a result of these three possible
   associations at least one of each child element MUST occur.
   Children:
      * <define-term> +
      * <definition> +

   Attributes:
      * core attributes 0





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5.5.3. <define-term> Tag
   This tag is intended to contain a single term, phrase, or clause to
   be defined.  The value for this tag MUST be whitespace normalized
   text.

   Attributes:
      * core attributes plus uri 0
      * internationalization attributes 0

5.5.4. <definition> Tag
   This tag is intended to contain the definition text that defines the
   associated terms.  The value for this tag can be text and inline
   elements.
   Children:
      * inline elements 0+

   Attributes:
      * core attributes 0
      * internationalization attributes 0

5.5.5. <navigation-list> Tag
   The <navigation-list> tag establishes a list of items that exist to
   either direct traffic or create a menu of URIs.  This tag allows for
   either a heading or a set of descriptive text and at least one
   navigation item.
   Children:
      * <heading> 0 or <identifier> 0
      * <navigation-item> +

   Attributes:
      * core attributes 0

5.5.6. <navigation-item> Tag
   This element is a single instance of navigation in a list of
   navigation choices.  This element may contain either an object for
   navigation or text for navigation as determined by its child tags.
   A uri attribute is REQUIRED on this element.
   Children:
      * <navigation-object> or <navigation-text>

   Attributes:
      * core attributes 0
      * uri

5.5.7. <navigation-object> Tag
   The <navigation-object> is a standard <object> that is modified to
   not allow use of the uri attribute.  This tag SHOULD only be used if
   the focus of navigation for the <navigation-item> of concern is an
   external resource expected to be processed into the content of the



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   message body.  Three children elements are REQUIRED.  For information
   on the child elements see sections 5.5.25. <object-text> Tag, 5.5.26.
   <object-uri> Tag, and 5.5.27. <object-type> Tag.

   It is important that an object contain text content that describes
   its resource.  There is no requirement for MML processors to process
   any external resource.  If the resource does fail to process the text
   contained by the object MUST display.
   Children:
      * <object-text>
      * <object-uri>
      * <object-type>

   Attributes:
      * core attributes 0
      * internationalization attributes 0

5.5.8. <navigation-text> Tag
   This element contains text and whitespace that is the focus of a
   navigation item.  This tag has no child elements.
   Attributes:
      * core attributes 0
      * internationalization attributes 0

5.5.9. <order-list> Tag
   An ordered list is a list where each item in that list is enumerated
   in the meta-data so that the position of elements in the list
   relative to other list items is valid data.  Whether or not this
   enumeration appears is to a human reader is strictly a presentation
   concern.  This element is allowed descriptive text in the form of a
   <heading> or <identifier> child.  Each item in the list MUST exist
   in the <list-item> child.  An example of a list that must be ordered
   is step-by-step directions, such as a recipie.
   Children:
      * <heading> 0 or <identifier> 0
      * <list-item> +

   Attributes:
      * core attributes 0

5.5.10. <unorder-list> Tag
   An unordered list is nearly identical to an ordered list except that
   list items are not enumerated.  This means position of items in the
   list is irrelevant.
   Children:
      * <heading> 0 or <identifier> 0
      * <list-item> +

   Attributes:
      * core attributes 0

	
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5.5.11. <list-item> Tag
   This element represents a single listed instantiation in a either an
   ordered or unordered list.  This element may contain a single simple
   block element or text plus 0 or more inline elements.
   Children:
      * simple block element or text plus inline elements 0+

   Attributes:
      * core attributes 0
      * internationalization attributes 0

5.5.12. <form> Tag
   The <form> tag is the high level parent container of a form.  A form
   allows organized controls upon input and submission of information in
   various methods allowed by the XForms standard.
   Children:
      * <model> (XForms)
      * <form-body>

5.5.13. <form-body>
   The <form-body> element is intended to contain all the form controls
   that a user could interact with plus other MML elements.
   Children:
      * <define-list> 0+
      * <navigation-list> 0+
      * <order-list> 0+
      * <unorder-list> 0+
      * <table> 0+
      * simple blocks 0+
      * form controls 0+ (XForms)

5.5.14. <table> Tag
   The <table> element allows authors to store and organize data in a
   grid or chart fashion.
   Children:
      * <head-row> 0
      * <table-row> +

   Attributes:
      * core attributes 0

5.5.15. <head-row> Tag
   The header row is a container of header cells to provide meta-data
   for tables.
   Child:
      * <head-cell> +

   Attributes:
      * core attributes 0



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5.5.16. <table-row> Tag
   A <table-row> MAY carry header cells or standard table cells.  A
   row is the standard unit of organization in a MML table.
   Children:
      * <head-cell> + or <table-cell> +

   Attributes:
      * core attributes 0

5.5.17. <head-cell> Tag
   A header cell provides meta-data that either labels or describes the
   data contained within its scope.  The scope of the header cell is
   determined by use of the scope attribute.  See section 5.4.13. scope
   Attribute for more information.  A header cell MUST contain either a
   single simple block or text plus any number of inline elements.
   Children:
      * simple blocks 0 or text plus inline elements 0+

   Attributes:
      * cell attributes 0
      * core attributes 0
      * internationalization attributes 0
      * scope 0

5.5.18. <table-cell> Tag
   The table cell is the standard unit of data in a table.  A table cell
   is not intended to provide any meta-data about the table or the
   structure of the table.  A table cell is intended to provide data
   directly to the user.  A table cell MUST contain either a single
   complex block or text plus any number of inline elements.
   Children:
      * simple blocks 0 or text plus inline elements 0+

   Attributes:
      * cell attributes 0
      * core attributes 0
      * internationalization attributes 0

5.5.19. <section> Tag
   A section is a high level structural organization block.  This is the
   only complex block capable of containing itself, such as nesting.
   The intent of the <section> tag is to subdivide the markup into
   various smaller areas for content organization, separation, and
   semantics.
   Children:
      * complex blocks 0+ and/or simple blocks 0+

   Attributes:
      * core attributes 0



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5.5.20. <block-code> Tag
   The block code simple block is intended to convey and describe code.
   The contents of this container MUST NOT directly contain XML reserved
   characters.  An XML processor cannot be told to not process
   characters that construct its syntax.  These reserved characters can
   be used if they are escaped with a character entity reference.
   Unlike the <plain-text> tag it is the author's responsibility to
   ensure the contents of this element are properly encoded.  Improperly
   encoded reserved characters SHOULD expect a result of failure at
   validation.  The reserved characters and their corresponding
   character entity references are:
         Character   Hex           Name
         <           &#60;         &lt;
         >           &#62;         &gt;
         &           &#38;         &amp;
         "           &#34;         &quot;
         '           &#39;         &apos;
   Children:
      * text and inline elements 0+

   Attributes:
      * core attributes 0
      * internationalization attributes 0

5.5.21. <block-quote> Tag
   A block quote is a large quotation that MAY span several statements.
   This element can contain text and any number of inline elements.
   Children:
      * text and inline elements 0+

   Attributes:
      * core attributes 0
      * internationalization attributes 0

5.5.22. <citation> Tag
   A citation is a descriptive reference to a piece of information used
   in content by a session author.  The information referenced by the
   <citation> tag automatically points to the content that requires it
   by use of a REQUIRED id attribute, which is referred to by the inline
   tag <cite>.  See section 5.5.29 <cite> Tag.  This element contains
   text and any number of inline elements.
   Children:
      *text and inline elements 0+

   Attributes:
      * id
      * title 0
      * style 0
      * role 0
      * internationalization attributes 0


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5.5.23. <heading> Tag
   A heading is a short block of text that describes the content that is
   to follow.  The <heading> tag MUST contain text and MAY contain 0 or
   more inline elements.
   Children:
      * text and inline elements 0+

   Attributes:
      * core attributes 0
      * internationalization attributes 0

5.5.24. <object> Tag
   An object is any external resource that is intended to be processed
   among the content of the message body, such as an image or video.
   Objects have three REQUIRED child tags.

   It is important that an object contain text content that describes
   its resource.  It is OPTIONAL for MML processors to process any
   external resource.  If the resource fails to process according to the
   value of <object-type> the text contained by the object MUST display.
   Children:
      * <object-text>
      * <object-uri>
      * <object-type>
      * inline elements 0+

   Attributes:
      * core attributes
      * internationalization attributes

5.5.25. <object-text> Tag
   Object text is the alternative text content that is to be rendered as
   content if the object cannot be resolved or processed.

5.5.26. <object-uri> Tag
   This element MUST only contain a URI value and that URI MUST point to
   the location of a resource to appear in the message body.  This
   element allows no child elements or attributes.

5.5.27. <object-type> Tag
   This element is of type "mime-type".  The object pointed to by the
   sibling <object-uri> tag MUST be processed only according to the type
   specified by this tag.

5.5.28. <paragraph> Tag
   This element is the standard generic container of text and inline
   elements in a MML document.  This element represents a paragraph and
   text is most typically grouped in paragraphs.
   Children:
      * text and inline elements 0+


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   Attributes:
      * core attributes 0
      * internationalization attributes 0

5.5.29. <separator> Tag
   This element is intended for semantic and structural purposes only.
   Use of this element indicates a structural obstruction in the flow or
   organization of content within a single section.  This element MAY
   contain text, which would indicate or explain the nature or reasoning
   of separation mandated by use of this element.
   Children:
      * text and inline elements 0+

   Attributes:
      * core attributes 0
      * internationalization attributes 0

5.5.30. <short> Tag
   This inline element describes text that is a short-hand value, such
   as an abbreviation or acronym.
   Attributes:
      * long-form
      * core attributes plus uri 0

5.5.31. <button> Tag
   This element exists to encourage interaction from a user outside of a
   form.  This version of MML does not allow for client-side scripting,
   limiting the potential of a button, although a button MAY be able to
   interact with media that performs its own internal scripting, such as
   Flash media.
   Attributes:
      * refer 0
      * core attributes plus uri 0

5.5.32. <cite> Tag
   The <cite> tag is intended to contain text begging a citation.  The
   refer attribute is REQUIRED as it MUST point to the id attribute of a
   <citation> in the same <markup> section of the document.  The refer
   attribute on this element MAY act as a fragment URI to send users to
   the location of the targeted <citation> element in the session.
   Attributes:
      * refer
      * core attributes 0

5.5.33. <emphasis> Tag
   This tag indicates the text it contains is more important than other
   text of the same context.
   Attributes:
      * core attributes plus uri 0



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5.5.34. <identifier> Tag
   This element is intended to provide a text label that describes some
   other element.  This element has a REQUIRED attribute of refer so
   that it may refer to the id of the element it is attempting to
   describe.

   Attributes:
      * refer
      * core attributes plus uri 0

5.5.35. <quote> Tag
   This element indicates the content it contains is a quotation.
   Attributes:
      * core attributes plus uri 0

5.5.36. <format> Tag
   The format tag is a special tag.  This is the only tag in the entire
   MML tag set that is deliberately intended to provide no semantic
   data.  This tag is available to provide access to the core attributes
   without imposing semantic considerations.  A session author MAY need
   to apply style or a uri attribute to some text that is otherwise no
   different than the text around it.  This is also the only inline tag
   that MAY contain a child tag.
   Child:
      * <format> 0+

   Attributes:
      * core attributes plus uri 0

5.5.37. <strong> Tag
   This tag indicates the content it contains is begging attention
   regardless of the importantce or relevance of the content in its
   given context.
   Attributes:
      * core attributes plus uri 0

5.5.38. <title> Tag
   This element indicates either a person's official title or the title
   of a work.
   Attributes:
      * core attributes plus uri 0

6. Protocol Compatibility
   It is important to determine if there is any interference to existing
   communication protocols imposed by the formal structuring of data.
   This section intends to determine if there are any incompatibilities
   with existing protocol standards and not whether existing services
   fail.  It is anticipated there will likely be natural
   incompatibilities with existing technology that MAY perform
   sophisticated processing and relay of data across a network without
   expectation to uniformity to the definitions imposed upon that data.

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   Application oriented concerns not defined by this specification,
   especially vender-specific concerns, exceed the scope of this
   specification.  If the standard imposed by this specification is not
   incompatible with existing standards it will be necessary for
   software vendors to modify their applications to ensure support of
   this technology without service interference.

   This section will explore considerations for the gathering of data
   from a MML document necessary to conduct transportation of the
   document.  This section is subdivided by mail distribution protocol.

6.1. Simple Mail Transfer Protocol (SMTP)
   SMTP [RFC5321] is the backbone protocol of email distribution.  This
   protocol is responsible for sending all email and often for receiving
   mail.  In order to be compatible to the requirements of RFC 5321
   (SMTP) RFC 5322 (Format) MUST be obsolete by this document.  This
   specification seeks to replace RFC 5322 as the standard method for
   describing data in email.

   RFC 5321 sets specific methods and requirements for the use of header
   fields from a mail document for use in defining transport and
   response necessary information.  There is no guidance specified for
   precise movement of header information from a document to protocol
   use under any particular circumstances.  The result is that MML
   processors MUST extract header information from the concerned header
   tags in a way that it deems most efficient and convenient to its
   logic so long as transport can be achieved in accordance with RFC
   5321 and without harm to the document.  Please see section 3. The
   SMTP Procedures: An Overview and Appendix B. Generating SMTP Commands
   from RFC 822 Headers from RFC 5321 for specific details.

6.2. Post Office Protocol - Version 3 (POP3)
   POP3 [RFC1939] is incompatible with this specification due its
   section 11. Message Format.  RFC 5322 is obsoleted by this document.
   POP3 is therefore incompatible by direct result of the following
   statement:

   "All messages transmitted during a POP3 session are assumed to
   conform to the standard for the format of Internet text messages
   [RFC822]."
   It is important to note that RFC 822 is obsoleted by RFC 5322.

   The result is that RFC 1939 MUST be obsolete.  If POP is to remain a
   standard it MUST be revised to either expect header information in
   MML specific format or be format non-specific.

6.3. Internet Message Access Protocol - Version 4rev1 (IMAP)
   IMAP [RFC3501] is inherently dependant on formatting specified by RFC
   5322, and so it MUST be rendered obsolete as a result.



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6.4. Requirements for Web Mail
   At this time of this writing Web Mail is inherently dependant upon
   POP3 and/or IMAP protocols.  Since these protocols are rendered
   obsolete by this specification it can be assumed that MML is
   incompatible with web mail as it exists during the time of this
   writing.

   In order for MML to be compatible with web mail the following
   conditions, beyond protocol compatibility, MUST be enforced:

      * The containing document, such as a page of Extensible Hypertext
      Markup Language ((X)HTML), MUST be served, processed, and rendered
      as a subset of XML.

      * The MML processor specific requirements specified in section 4.
      Processor Roles are REQUIRED.

      * Components of the containing document, such as a page of
      (X)HTML, MUST NOT mix or interfere with the MML code.  MML, and
      its subsets; if any, MUST exist as a preserved code island.

      * MML MUST be sent without interference or supplication to its
      code or structure from its containing document, as a page of
      (X)HTML.

      * Scripting that exists or is allowed by a containing document,
      such as a page of (X)HTML, MUST NOT be allowed to execute against
      the code, content, or structure imposed by the MML code island.

      * MML presentation requirements MUST be enforced.  Presentation
      from the containing document, such as a page of (X)HTML, MUST NOT
      act upon or interfere with presentation imposed by MML referenced
      stylesheets.  The containing page MAY establish lowest priority
      default presentation exactly as a MML processor MAY do so.

      * The containing document MUST be served only to the authorized
      user through an encrypted transmission.

      * An XML compliant web browser SHOULD be capable of processing,
      presenting, and transmitting a MML document without any need for a
      containing document or any use of HTML or reformulation thereof.

7. Default mime.xsd
<?xml version="1.0" encoding="utf-8" ?>
<xs:schema elementFormDefault="qualified" version="1.0"
xmlns:xs="http://www.w3.org/2001/XMLSchema">
  <xs:simpleType name="application-type">
    <xs:restriction base="xs:token">
      <xs:enumeration value="activemessage" />
      <xs:enumeration value="andrew-inset" />
      <xs:enumeration value="applefile" />

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      <xs:enumeration value="atom+xml" />
      <xs:enumeration value="atomicmail" />
      <xs:enumeration value="atomcat+xml" />
      <xs:enumeration value="atomsvc+xml" />
      <xs:enumeration value="auth-policy+xml" />
      <xs:enumeration value="batch-SMTP" />
      <xs:enumeration value="beep+xml" />
      <xs:enumeration value="cals-1840" />
      <xs:enumeration value="ccxml+xml" />
      <xs:enumeration value="cellml+xml" />
      <xs:enumeration value="cnrp+xml" />
      <xs:enumeration value="commonground" />
      <xs:enumeration value="conference-info+xml" />
      <xs:enumeration value="cpl+xml" />
      <xs:enumeration value="csta+xml" />
      <xs:enumeration value="CSTAdata+xml" />
      <xs:enumeration value="cybercash" />
      <xs:enumeration value="davmount+xml" />
      <xs:enumeration value="dca-rft" />
      <xs:enumeration value="dec-dx" />
      <xs:enumeration value="dialog-info+xml" />
      <xs:enumeration value="dicom" />
      <xs:enumeration value="dns" />
      <xs:enumeration value="dvcs" />
      <xs:enumeration value="ecmascript" />
      <xs:enumeration value="EDI-Consent" />
      <xs:enumeration value="EDIFACT" />
      <xs:enumeration value="EDI-X12" />
      <xs:enumeration value="epp+xml" />
      <xs:enumeration value="eshop" />
      <xs:enumeration value="example" />
      <xs:enumeration value="fastinfoset" />
      <xs:enumeration value="fastsoap" />
      <xs:enumeration value="fits" />
      <xs:enumeration value="font-tdpfr" />
      <xs:enumeration value="H224" />
      <xs:enumeration value="http" />
      <xs:enumeration value="hyperstudio" />
      <xs:enumeration value="iges" />
      <xs:enumeration value="im-iscomposing+xml" />
      <xs:enumeration value="index" />
      <xs:enumeration value="index.cmd" />
      <xs:enumeration value="index.obj" />
      <xs:enumeration value="index.response" />
      <xs:enumeration value="index.vnd" />
      <xs:enumeration value="iotp" />
      <xs:enumeration value="ipp" />
      <xs:enumeration value="isup" />
      <xs:enumeration value="javascript" />
      <xs:enumeration value="json" />
      <xs:enumeration value="kpml-request+xml" />

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      <xs:enumeration value="kpml-response+xml" />
      <xs:enumeration value="lost+xml" />
      <xs:enumeration value="mac-binhex40" />
      <xs:enumeration value="macwriteii" />
      <xs:enumeration value="marc" />
      <xs:enumeration value="mathematica" />
      <xs:enumeration
      value="mbms-associated-procedure-description+xml" />
      <xs:enumeration value="mbms-deregister+xml" />
      <xs:enumeration value="mbms-envelope+xml" />
      <xs:enumeration value="mbms-msk-response+xml" />
      <xs:enumeration value="mbms-msk+xml" />
      <xs:enumeration value="mbms-protection-description+xml" />
      <xs:enumeration value="mbms-reception-report+xml" />
      <xs:enumeration value="mbms-register-response+xml" />
      <xs:enumeration value="mbms-register+xml" />
      <xs:enumeration value="mbms-user-service-description+xml" />
      <xs:enumeration value="mbox" />
      <xs:enumeration value="media_control+xml" />
      <xs:enumeration value="mediaservercontrol+xml" />
      <xs:enumeration value="mikey" />
      <xs:enumeration value="moss-keys" />
      <xs:enumeration value="moss-signature" />
      <xs:enumeration value="mosskey-data" />
      <xs:enumeration value="mosskey-request" />
      <xs:enumeration value="mpeg4-generic" />
      <xs:enumeration value="mpeg4-iod" />
      <xs:enumeration value="mpeg4-iod-xmt" />
      <xs:enumeration value="mp4" />
      <xs:enumeration value="msword" />
      <xs:enumeration value="mxf" />
      <xs:enumeration value="nasdata" />
      <xs:enumeration value="news-transmission" />
      <xs:enumeration value="nss" />
      <xs:enumeration value="ocsp-request" />
      <xs:enumeration value="ocsp-response" />
      <xs:enumeration value="octet-stream" />
      <xs:enumeration value="oda" />
      <xs:enumeration value="oebps-package+xml" />
      <xs:enumeration value="ogg" />
      <xs:enumeration value="parityfec" />
      <xs:enumeration value="patch-ops-error+xml" />
      <xs:enumeration value="pdf" />
      <xs:enumeration value="pgp-encrypted" />
      <xs:enumeration value="pgp-keys" />
      <xs:enumeration value="pgp-signature" />
      <xs:enumeration value="pidf+xml" />
      <xs:enumeration value="pidf-diff+xml" />
      <xs:enumeration value="pkcs10" />
      <xs:enumeration value="pkcs7-mime" />
      <xs:enumeration value="pkcs7-signature" />

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      <xs:enumeration value="pkix-cert" />
      <xs:enumeration value="pkixcmp" />
      <xs:enumeration value="pkix-crl" />
      <xs:enumeration value="pkix-pkipath" />
      <xs:enumeration value="pls+xml" />
      <xs:enumeration value="poc-settings+xml" />
      <xs:enumeration value="postscript" />
      <xs:enumeration value="prs.alvestrand.titrax-sheet" />
      <xs:enumeration value="prs.cww" />
      <xs:enumeration value="prs.nprend" />
      <xs:enumeration value="prs.plucker" />
      <xs:enumeration value="qsig" />
      <xs:enumeration value="rdf+xml" />
      <xs:enumeration value="reginfo+xml" />
      <xs:enumeration value="relax-ng-compact-syntax" />
      <xs:enumeration value="remote-printing" />
      <xs:enumeration value="resource-lists+xml" />
      <xs:enumeration value="riscos" />
      <xs:enumeration value="rlmi+xml" />
      <xs:enumeration value="rls-services+xml" />
      <xs:enumeration value="rtf" />
      <xs:enumeration value="rtx" />
      <xs:enumeration value="samlassertion+xml" />
      <xs:enumeration value="samlmetadata+xml" />
      <xs:enumeration value="sbml+xml" />
      <xs:enumeration value="scvp-cv-request" />
      <xs:enumeration value="scvp-cv-response" />
      <xs:enumeration value="scvp-vp-request" />
      <xs:enumeration value="scvp-vp-response" />
      <xs:enumeration value="sdp" />
      <xs:enumeration value="set-payment" />
      <xs:enumeration value="set-payment-initiation" />
      <xs:enumeration value="set-registration" />
      <xs:enumeration value="set-registration-initiation" />
      <xs:enumeration value="sgml" />
      <xs:enumeration value="sgml-open-catalog" />
      <xs:enumeration value="shf+xml" />
      <xs:enumeration value="sieve" />
      <xs:enumeration value="simple-filter+xml" />
      <xs:enumeration value="simple-message-summary" />
      <xs:enumeration value="simpleSymbolContainer" />
      <xs:enumeration value="slate" />
      <xs:enumeration value="smil+xml" />
      <xs:enumeration value="soap+fastinfoset" />
      <xs:enumeration value="soap+xml" />
      <xs:enumeration value="sparql-query" />
      <xs:enumeration value="sparql-results+xml" />
      <xs:enumeration value="spirits-event+xml" />
      <xs:enumeration value="srgs" />
      <xs:enumeration value="srgs+xml" />
      <xs:enumeration value="ssml+xml" />

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      <xs:enumeration value="timestamp-query" />
      <xs:enumeration value="timestamp-reply" />
      <xs:enumeration value="tve-trigger" />
      <xs:enumeration value="ulpfec" />
      <xs:enumeration value="vemmi" />
      <xs:enumeration value="vnd.3gpp.bsf+xml" />
      <xs:enumeration value="vnd.3gp.pic-bw-large" />
      <xs:enumeration value="vnd.3gp.pic-bw-small" />
      <xs:enumeration value="vnd.3gp.pic-bw-var" />
      <xs:enumeration value="vnd.3gp.sms" />
      <xs:enumeration value="vnd.3gp2.bcmcsinfo+xml" />
      <xs:enumeration value="vnd.3gp2.sms" />
      <xs:enumeration value="vnd.3gp2.tcap" />
      <xs:enumeration value="vnd.3M.Post-in-Notes" />
      <xs:enumeration value="vnd.accpac.simply.aso" />
      <xs:enumeration value="vnd.accpac.simply.imp" />
      <xs:enumeration value="vnd.acucobol" />
      <xs:enumeration value="vnd.acucorp" />
      <xs:enumeration value="vnd.adobe.xdp+xml" />
      <xs:enumeration value="vnd.adobe.xfdf" />
      <xs:enumeration value="vnd.aether.imp" />
      <xs:enumeration value="vnd.americandynamics.acc" />
      <xs:enumeration value="vnd.amiga.ami" />
      <xs:enumeration
      value="vnd.anser-web-certificate-issue-initiation" />
      <xs:enumeration value="vnd.antix.game-component" />
      <xs:enumeration value="vnd.apple.installer+xml" />
      <xs:enumeration value="vnd.arastra.swi" />
      <xs:enumeration value="vnd.audiograph" />
      <xs:enumeration value="vnd.autopackage" />
      <xs:enumeration value="vnd.avistar+xml" />
      <xs:enumeration value="vnd.blueice.multipass" />
      <xs:enumeration value="vnd.bmi" />
      <xs:enumeration value="vnd.businessobjects" />
      <xs:enumeration value="vnd.cab-jscript" />
      <xs:enumeration value="vnd.canon-cpdl" />
      <xs:enumeration value="vnd.canon-lips" />
      <xs:enumeration value="vnd.cendio.thinlinc.clientconf" />
      <xs:enumeration value="vnd.chemdraw+xml" />
      <xs:enumeration value="vnd.chipnuts.karaoke-mmd" />
      <xs:enumeration value="vnd.cinderella" />
      <xs:enumeration value="vnd.cirpack.isdn-ext" />
      <xs:enumeration value="vnd.claymore" />
      <xs:enumeration value="vnd.clonk.c4group" />
      <xs:enumeration value="vnd.commerce-battelle" />
      <xs:enumeration value="vnd.comonspace" />
      <xs:enumeration value="vnd.cosmocaller" />
      <xs:enumeration value="vnd.contact.cmsg" />
      <xs:enumeration value="vnd.crick.clicker" />
      <xs:enumeration value="vnd.crick.clicker.keyboard" />
      <xs:enumeration value="vnd.crick.clicker.palette" />

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      <xs:enumeration value="vnd.crick.clicker.template" />
      <xs:enumeration value="vnd.crick.clicker.wordbank" />
      <xs:enumeration value="vnd.criticaltools.wbs+xml" />
      <xs:enumeration value="vnd.ctc-posml" />
      <xs:enumeration value="vnd.ctct.ws+xml" />
      <xs:enumeration value="vnd.cups-pdf" />
      <xs:enumeration value="vnd.cups-postscript" />
      <xs:enumeration value="vnd.cups-ppd" />
      <xs:enumeration value="vnd.cups-raster" />
      <xs:enumeration value="vnd.cups-raw" />
      <xs:enumeration value="vnd.curl" />
      <xs:enumeration value="vnd.cybank" />
      <xs:enumeration value="vnd.data-vision.rdf" />
      <xs:enumeration value="vnd.denovo.fcselayout-link" />
      <xs:enumeration value="vnd.dna" />
      <xs:enumeration value="vnd.dpgraph" />
      <xs:enumeration value="vnd.dreamfactory" />
      <xs:enumeration value="vnd.dvb.esgcontainer" />
      <xs:enumeration value="vnd.dvb.ipdcesgaccess" />
      <xs:enumeration value="vnd.dvb.iptv.alfec-base" />
      <xs:enumeration value="vnd.dvb.iptv.alfec-enhancement" />
      <xs:enumeration value="vnd.dxr" />
      <xs:enumeration value="vnd.ecdis-update" />
      <xs:enumeration value="vnd.ecowin.chart" />
      <xs:enumeration value="vnd.ecowin.filerequest" />
      <xs:enumeration value="vnd.ecowin.fileupdate" />
      <xs:enumeration value="vnd.ecowin.series" />
      <xs:enumeration value="vnd.ecowin.seriesrequest" />
      <xs:enumeration value="vnd.ecowin.seriesupdate" />
      <xs:enumeration value="vnd.enliven" />
      <xs:enumeration value="vnd.epson.esf" />
      <xs:enumeration value="vnd.epson.msf" />
      <xs:enumeration value="vnd.epson.quickanime" />
      <xs:enumeration value="vnd.epson.salt" />
      <xs:enumeration value="vnd.epson.ssf" />
      <xs:enumeration value="vnd.ericsson.quickcall" />
      <xs:enumeration value="vnd.eszigno3+xml" />
      <xs:enumeration value="vnd.eudora.data" />
      <xs:enumeration value="vnd.ezpix-album" />
      <xs:enumeration value="vnd.fdf" />
      <xs:enumeration value="vnd.ffsns" />
      <xs:enumeration value="vnd.fints" />
      <xs:enumeration value="vnd.FloGraphIt" />
      <xs:enumeration value="vnd.fluxtime.clip" />
      <xs:enumeration value="vnd.font-fontforge-sfd" />
      <xs:enumeration value="vnd.framemaker" />
      <xs:enumeration value="vnd.frogans.fnc" />
      <xs:enumeration value="vnd.frogans.ltf" />
      <xs:enumeration value="vnd.fsc.weblaunch" />
      <xs:enumeration value="vnd.fujitsu.oasys" />
      <xs:enumeration value="vnd.fujitsu.oasys2" />

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      <xs:enumeration value="vnd.fujitsu.oasys3" />
      <xs:enumeration value="vnd.fujitsu.oasysgp" />
      <xs:enumeration value="vnd.fujitsu.oasysprs" />
      <xs:enumeration value="vnd.fujixerox.ART4" />
      <xs:enumeration value="vnd.fujixerox.ART-EX" />
      <xs:enumeration value="vnd.fujixerox.ddd" />
      <xs:enumeration value="vnd.fujixerox.docuworks" />
      <xs:enumeration value="vnd.fujixerox.docuworks.binder" />
      <xs:enumeration value="vnd.fujixerox.HBPL" />
      <xs:enumeration value="vnd.fut-misnet" />
      <xs:enumeration value="vnd.fuzzysheet" />
      <xs:enumeration value="vnd.genomatix.tuxedo" />
      <xs:enumeration value="vnd.google-earth.kml+xml" />
      <xs:enumeration value="vnd.google-earth.kmz" />
      <xs:enumeration value="vnd.grafeq" />
      <xs:enumeration value="vnd.gridmp" />
      <xs:enumeration value="vnd.groove-account" />
      <xs:enumeration value="vnd.groove-help" />
      <xs:enumeration value="vnd.groove-identity-message" />
      <xs:enumeration value="vnd.groove-injector" />
      <xs:enumeration value="vnd.groove-tool-message" />
      <xs:enumeration value="vnd.groove-tool-template" />
      <xs:enumeration value="vnd.groove-vcard" />
      <xs:enumeration value="vnd.HandHeld-Entertainment+xml" />
      <xs:enumeration value="vnd.hbci" />
      <xs:enumeration value="vnd.hcl-bireports" />
      <xs:enumeration value="vnd.hhe.lesson-player" />
      <xs:enumeration value="vnd.hp-HPGL" />
      <xs:enumeration value="vnd.hp-hpid" />
      <xs:enumeration value="vnd.hp-hps" />
      <xs:enumeration value="vnd.hp-jlyt" />
      <xs:enumeration value="vnd.hp-PCL" />
      <xs:enumeration value="vnd.hp-PCLXL" />
      <xs:enumeration value="vnd.httphone" />
      <xs:enumeration value="vnd.hydrostatix.sof-data" />
      <xs:enumeration value="vnd.hzn-3d-crossword" />
      <xs:enumeration value="vnd.ibm.afplinedata" />
      <xs:enumeration value="vnd.ibm.electronic-media" />
      <xs:enumeration value="vnd.ibm.MiniPay" />
      <xs:enumeration value="vnd.ibm.modcap" />
      <xs:enumeration value="vnd.ibm.rights-management" />
      <xs:enumeration value="vnd.ibm.secure-container" />
      <xs:enumeration value="vnd.iccprofile" />
      <xs:enumeration value="vnd.igloader" />
      <xs:enumeration value="vnd.immervision-ivp" />
      <xs:enumeration value="vnd.immervision-ivu" />
      <xs:enumeration value="vnd.informedcontrol.rms+xml" />
      <xs:enumeration value="vnd.informix-visionary" />
      <xs:enumeration value="vnd.intercon.formnet" />
      <xs:enumeration value="vnd.intertrust.digibox" />
      <xs:enumeration value="vnd.intertrust.nncp" />

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      <xs:enumeration value="vnd.intu.qbo" />
      <xs:enumeration value="vnd.intu.qfx" />
      <xs:enumeration value="vnd.iptc.g2.conceptitem+xml" />
      <xs:enumeration value="vnd.iptc.g2.knowledgeitem+xml" />
      <xs:enumeration value="vnd.iptc.g2.newsitem+xml" />
      <xs:enumeration value="vnd.iptc.g2.packageitem+xml" />
      <xs:enumeration value="vnd.ipunplugged.rcprofile" />
      <xs:enumeration value="vnd.irepository.package+xml" />
      <xs:enumeration value="vnd.is-xpr" />
      <xs:enumeration value="vnd.jam" />
      <xs:enumeration value="vnd.japannet-directory-service" />
      <xs:enumeration value="vnd.japannet-ipnstore-wakeup" />
      <xs:enumeration value="vnd.japannet-payment-wakeup" />
      <xs:enumeration value="vnd.japannet-registration" />
      <xs:enumeration value="vnd.japannet-registration-wakeup" />
      <xs:enumeration value="vnd.japannet-setstore-wakeup" />
      <xs:enumeration value="vnd.japannet-verification" />
      <xs:enumeration value="vnd.japannet-japannet--wakeup" />
      <xs:enumeration value="vnd.jcp.javame.midlet-rms" />
      <xs:enumeration value="vnd.jisp" />
      <xs:enumeration value="vnd.joost.joda-archive" />
      <xs:enumeration value="vnd.kahootz" />
      <xs:enumeration value="vnd.kde.karbon" />
      <xs:enumeration value="vnd.kde.kchart" />
      <xs:enumeration value="vnd.kde.kformula" />
      <xs:enumeration value="vnd.kde.kivio" />
      <xs:enumeration value="vnd.kde.kontour" />
      <xs:enumeration value="vnd.kde.kpresenter" />
      <xs:enumeration value="vnd.kde.kspread" />
      <xs:enumeration value="vnd.kde.kword" />
      <xs:enumeration value="vnd.kenameaapp" />
      <xs:enumeration value="vnd.kidspiration" />
      <xs:enumeration value="vnd.Kinar" />
      <xs:enumeration value="vnd.koan" />
      <xs:enumeration value="vnd.kodak-descriptor" />
      <xs:enumeration value="vnd.liberty-request+xml" />
      <xs:enumeration value="vnd.llamagraphics.life-balance.desktop" />
      <xs:enumeration
      value="vnd.llamagraphics.life-balance.exchange+xml" />
      <xs:enumeration value="vnd.lotus-1-2-3" />
      <xs:enumeration value="vnd.lotus-approach" />
      <xs:enumeration value="vnd.lotus-freelance" />
      <xs:enumeration value="vnd.lotus-notes" />
      <xs:enumeration value="vnd.lotus-organizer" />
      <xs:enumeration value="vnd.lotus-screencam" />
      <xs:enumeration value="vnd.lotus-wordpro" />
      <xs:enumeration value="vnd.macports.portpkg" />
      <xs:enumeration value="vnd.marlin.drm.actiontoken+xml" />
      <xs:enumeration value="vnd.marlin.drm.conftoken+xml" />
      <xs:enumeration value="vnd.marlin.drm.license+xml" />
      <xs:enumeration value="vnd.marlin.drm.mdcf" />

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      <xs:enumeration value="vnd.mcd" />
      <xs:enumeration value="vnd.medcalcdata" />
      <xs:enumeration value="vnd.mediastation.cdkey" />
      <xs:enumeration value="vnd.meridian-slingshot" />
      <xs:enumeration value="vnd.MFER" />
      <xs:enumeration value="vnd.mfmp" />
      <xs:enumeration value="vnd.micrografx.flo" />
      <xs:enumeration value="vnd.micrografx.igx" />
      <xs:enumeration value="vnd.mif" />
      <xs:enumeration value="vnd.minisoft-hp3000-save" />
      <xs:enumeration value="vnd.mitsubishi.misty-guard.trustweb" />
      <xs:enumeration value="vnd.Mobius.DAF" />
      <xs:enumeration value="vnd.Mobius.DIS" />
      <xs:enumeration value="vnd.Mobius.MBK" />
      <xs:enumeration value="vnd.Mobius.MQY" />
      <xs:enumeration value="vnd.Mobius.MSL" />
      <xs:enumeration value="vnd.Mobius.PLC" />
      <xs:enumeration value="vnd.Mobius.TXF" />
      <xs:enumeration value="vnd.mophun.application" />
      <xs:enumeration value="vnd.mophun.certificate" />
      <xs:enumeration value="vnd.motorola.flexsuite" />
      <xs:enumeration value="vnd.motorola.flexsuite.adsi" />
      <xs:enumeration value="vnd.motorola.flexsuite.fis" />
      <xs:enumeration value="vnd.motorola.flexsuite.gotap" />
      <xs:enumeration value="vnd.motorola.flexsuite.kmr" />
      <xs:enumeration value="vnd.motorola.flexsuite.ttc" />
      <xs:enumeration value="vnd.motorola.flexsuite.wem" />
      <xs:enumeration value="vnd.mozilla.xul+xml" />
      <xs:enumeration value="vnd.ms-artgalry" />
      <xs:enumeration value="vnd.ms-asf" />
      <xs:enumeration value="vnd.ms-cab-compressed" />
      <xs:enumeration value="vnd.ms-excel" />
      <xs:enumeration value="vnd.ms-fontobject" />
      <xs:enumeration value="vnd.ms-htmlhelp" />
      <xs:enumeration value="vnd.ms-ims" />
      <xs:enumeration value="vnd.ms-lrm" />
      <xs:enumeration value="vnd.ms-playready.initiator+xml" />
      <xs:enumeration value="vnd.ms-powerpoint" />
      <xs:enumeration value="vnd.ms-project" />
      <xs:enumeration value="vnd.ms-tnef" />
      <xs:enumeration value="vnd.ms-wmdrm.lic-chlg-req" />
      <xs:enumeration value="vnd.ms-wmdrm.lic-resp" />
      <xs:enumeration value="vnd.ms-wmdrm.meter-chlg-req" />
      <xs:enumeration value="vnd.ms-wmdrm.meter-resp" />
      <xs:enumeration value="vnd.ms-works" />
      <xs:enumeration value="vnd.ms-wpl" />
      <xs:enumeration value="vnd.ms-xpsdocument" />
      <xs:enumeration value="vnd.mseq" />
      <xs:enumeration value="vnd.msign" />
      <xs:enumeration value="vnd.multiad.creator" />
      <xs:enumeration value="vnd.multiad.creator.cif" />

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      <xs:enumeration value="vnd.musician" />
      <xs:enumeration value="vnd.music-niff" />
      <xs:enumeration value="vnd.muvee.style" />
      <xs:enumeration value="vnd.ncd.control" />
      <xs:enumeration value="vnd.ncd.reference" />
      <xs:enumeration value="vnd.nervana" />
      <xs:enumeration value="vnd.netfpx" />
      <xs:enumeration value="vnd.neurolanguage.nlu" />
      <xs:enumeration value="vnd.noblenet-directory" />
      <xs:enumeration value="vnd.noblenet-sealer" />
      <xs:enumeration value="vnd.noblenet-web" />
      <xs:enumeration value="vnd.nokia.catalogs" />
      <xs:enumeration value="vnd.nokia.conml+wbxml" />
      <xs:enumeration value="vnd.nokia.conml+xml" />
      <xs:enumeration value="vnd.nokia.iptv.config+xml" />
      <xs:enumeration value="vnd.nokia.iSDS-radio-presets" />
      <xs:enumeration value="vnd.nokia.landmark+xml" />
      <xs:enumeration value="vnd.nokia.landmarkcollection+xml" />
      <xs:enumeration value="vnd.nokia.ncd" />
      <xs:enumeration value="vnd.nokia.n-gage.ac+xml" />
      <xs:enumeration value="vnd.nokia.n-gage.data" />
      <xs:enumeration value="vnd.nokia.n-gage.symbian.install" />
      <xs:enumeration value="vnd.nokia.pcd+wbxml" />
      <xs:enumeration value="vnd.nokia.pcd+xml" />
      <xs:enumeration value="vnd.nokia.radio-preset" />
      <xs:enumeration value="vnd.nokia.radio-presets" />
      <xs:enumeration value="vnd.novadigm.EDM" />
      <xs:enumeration value="vnd.novadigm.EDX" />
      <xs:enumeration value="vnd.novadigm.EXT" />
      <xs:enumeration value="vnd.oasis.opendocument.chart" />
      <xs:enumeration value="vnd.oasis.opendocument.chart-template" />
      <xs:enumeration value="vnd.oasis.opendocument.formula" />
      <xs:enumeration value="vnd.oasis.opendocument.formula-template" />
      <xs:enumeration value="vnd.oasis.opendocument.graphics" />
      <xs:enumeration
      value="vnd.oasis.opendocument.graphics-template" />
      <xs:enumeration value="vnd.oasis.opendocument.image" />
      <xs:enumeration value="vnd.oasis.opendocument.image-template" />
      <xs:enumeration value="vnd.oasis.opendocument.presentation" />
      <xs:enumeration
      value="vnd.oasis.opendocument.presentation-template" />
      <xs:enumeration value="vnd.oasis.opendocument.spreadsheet" />
      <xs:enumeration
      value="vnd.oasis.opendocument.spreadsheet-template" />
      <xs:enumeration value="vnd.oasis.opendocument.text" />
      <xs:enumeration value="vnd.oasis.opendocument.text-master" />
      <xs:enumeration value="vnd.oasis.opendocument.text-template" />
      <xs:enumeration value="vnd.oasis.opendocument.text-web" />
      <xs:enumeration value="vnd.obn" />
      <xs:enumeration value="vnd.olpc-sugar" />
      <xs:enumeration

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      value="vnd.oma.bcast.asssociated-procedure-parameter+xml" />
      <xs:enumeration value="vnd.oma.bcast.drm-trigger+xml" />
      <xs:enumeration value="vnd.oma.bcast.imd+xml" />
      <xs:enumeration value="vnd.oma.bcast.ltkm" />
      <xs:enumeration value="vnd.oma.bcast.notification+xml" />
      <xs:enumeration value="vnd.oma.bcast.sgboot" />
      <xs:enumeration value="vnd.oma.bcast.sgdd+xml" />
      <xs:enumeration value="vnd.oma.bcast.sgdu" />
      <xs:enumeration value="vnd.oma.bcast.simple-symbol-container" />
      <xs:enumeration value="vnd.oma.bcast.smartcard-trigger+xml" />
      <xs:enumeration value="vnd.oma.bcast.sprov+xml" />
      <xs:enumeration value="vnd.oma.bcast.stkm" />
      <xs:enumeration value="vnd.oma.dcd" />
      <xs:enumeration value="vnd.oma.dcdc" />
      <xs:enumeration value="vnd.oma.dd2+xml" />
      <xs:enumeration value="vnd.oma.drm.risd+xml" />
      <xs:enumeration value="vnd.oma.group-usage-list+xml" />
      <xs:enumeration
      value="vnd.oma.poc.detailed-progress-report+xml" />
      <xs:enumeration value="vnd.oma.poc.final-report+xml" />
      <xs:enumeration value="vnd.oma.groups+xml" />
      <xs:enumeration value="vnd.oma.invocation-descriptor+xml" />
      <xs:enumeration value="vnd.oma.optimized-progress-report+xml" />
      <xs:enumeration value="vnd.oma.xcap-directory+xml" />
      <xs:enumeration value="vnd.omads-email+xml" />
      <xs:enumeration value="vnd.omads-file+xml" />
      <xs:enumeration value="vnd.omads-folder+xml" />
      <xs:enumeration value="vnd.omaloc-sup-init" />
      <xs:enumeration value="vnd.oma-scws-http-request" />
      <xs:enumeration value="vnd.oma-scws-http-response" />
      <xs:enumeration value="vnd.openofficeorg.extension" />
      <xs:enumeration value="vnd.osa.netdeploy" />
      <xs:enumeration value="vnd.osgi.bundle" />
      <xs:enumeration value="vnd.osgi.dp" />
      <xs:enumeration value="vnd.otps.ct-kip+xml" />
      <xs:enumeration value="vnd.palm" />
      <xs:enumeration value="vnd.paos.xml" />
      <xs:enumeration value="vnd.pg.format" />
      <xs:enumeration value="vnd.pg.osasli" />
      <xs:enumeration value="vnd.piacess.application-license" />
      <xs:enumeration value="vnd.picsel" />
      <xs:enumeration value="vnd.poc.group-advertisement+xml" />
      <xs:enumeration value="vnd.pocketlearn" />
      <xs:enumeration value="vnd.powerbuilder6" />
      <xs:enumeration value="vnd.powerbuilder6-s" />
      <xs:enumeration value="vnd.powerbuilder7" />
      <xs:enumeration value="vnd.powerbuilder75" />
      <xs:enumeration value="vnd.powerbuilder75-s" />
      <xs:enumeration value="vnd.powerbuilder7-s" />
      <xs:enumeration value="vnd.preminet" />
      <xs:enumeration value="vnd.previewsystems.box" />

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      <xs:enumeration value="vnd.proteus.magazine" />
      <xs:enumeration value="vnd.publishare-delta-tree" />
      <xs:enumeration value="vnd.pvi.ptid1" />
      <xs:enumeration value="vnd.pwg-multiplexed" />
      <xs:enumeration value="vnd.pwg-xhtml-print+xml" />
      <xs:enumeration value="vnd.qualcomm.brew-app-res" />
      <xs:enumeration value="vnd.Quark.QuarkXPress" />
      <xs:enumeration value="vnd.rapid" />
      <xs:enumeration value="vnd.recordare.musicxml" />
      <xs:enumeration value="vnd.recordare.musicxml+xml" />
      <xs:enumeration value="vnd.RenLearn.rlprint" />
      <xs:enumeration value="vnd.route66.link66+xml" />
      <xs:enumeration value="vnd.ruckus.download" />
      <xs:enumeration value="vnd.s3sms" />
      <xs:enumeration value="vnd.sbm.cid" />
      <xs:enumeration value="vnd.sbm.mid2" />
      <xs:enumeration value="vnd.scribus" />
      <xs:enumeration value="vnd.sealed.3df" />
      <xs:enumeration value="vnd.sealed.csf" />
      <xs:enumeration value="vnd.sealed.doc" />
      <xs:enumeration value="vnd.sealed.eml" />
      <xs:enumeration value="vnd.sealed.mht" />
      <xs:enumeration value="vnd.sealed.net" />
      <xs:enumeration value="vnd.sealed.ppt" />
      <xs:enumeration value="vnd.sealed.tiff" />
      <xs:enumeration value="vnd.sealed.xls" />
      <xs:enumeration value="vnd.sealedmedia.softseal.html" />
      <xs:enumeration value="vnd.sealedmedia.softseal.pdf" />
      <xs:enumeration value="vnd.seemail" />
      <xs:enumeration value="vnd.sema" />
      <xs:enumeration value="vnd.semd" />
      <xs:enumeration value="vnd.semf" />
      <xs:enumeration value="vnd.shana.informed.formdata" />
      <xs:enumeration value="vnd.shana.informed.formtemplate" />
      <xs:enumeration value="vnd.shana.informed.interchange" />
      <xs:enumeration value="vnd.shana.informed.package" />
      <xs:enumeration value="vnd.SimTech-MindMapper" />
      <xs:enumeration value="vnd.smaf" />
      <xs:enumeration value="vnd.solent.sdkm+xml" />
      <xs:enumeration value="vnd.spotfire.dxp" />
      <xs:enumeration value="vnd.spotfire.sfs" />
      <xs:enumeration value="vnd.sss-cod" />
      <xs:enumeration value="vnd.sss-dtf" />
      <xs:enumeration value="vnd.sss-ntf" />
      <xs:enumeration value="vnd.street-stream" />
      <xs:enumeration value="vnd.sun.wadl+xml" />
      <xs:enumeration value="vnd.sus-calendar" />
      <xs:enumeration value="vnd.svd" />
      <xs:enumeration value="vnd.swiftview-ics" />
      <xs:enumeration value="vnd.syncml.dm+wbxml" />
      <xs:enumeration value="vnd.syncml.dm+xml" />

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      <xs:enumeration value="vnd.syncml.ds.notification" />
      <xs:enumeration value="vnd.syncml+xml" />
      <xs:enumeration value="vnd.tao.intent-module-archive" />
      <xs:enumeration value="vnd.tmobile-livetv" />
      <xs:enumeration value="vnd.trid.tpt" />
      <xs:enumeration value="vnd.triscape.mxs" />
      <xs:enumeration value="vnd.trueapp" />
      <xs:enumeration value="vnd.truedoc" />
      <xs:enumeration value="vnd.ufdl" />
      <xs:enumeration value="vnd.uig.theme" />
      <xs:enumeration value="vnd.umajin" />
      <xs:enumeration value="vnd.unity" />
      <xs:enumeration value="vnd.uoml+xml" />
      <xs:enumeration value="vnd.uplanet.alert" />
      <xs:enumeration value="vnd.uplanet.alert-wbxml" />
      <xs:enumeration value="vnd.uplanet.bearer-choice" />
      <xs:enumeration value="vnd.uplanet.bearer-choice-wbxml" />
      <xs:enumeration value="vnd.uplanet.cacheop" />
      <xs:enumeration value="vnd.uplanet.cacheop-wbxml" />
      <xs:enumeration value="vnd.uplanet.channel" />
      <xs:enumeration value="vnd.uplanet.channel-wbxml" />
      <xs:enumeration value="vnd.uplanet.list" />
      <xs:enumeration value="vnd.uplanet.listcmd" />
      <xs:enumeration value="vnd.uplanet.listcmd-wbxml" />
      <xs:enumeration value="vnd.uplanet.list-wbxml" />
      <xs:enumeration value="vnd.uplanet.signal" />
      <xs:enumeration value="vnd.vcx" />
      <xs:enumeration value="vnd.vectorworks" />
      <xs:enumeration value="vnd.vd-study" />
      <xs:enumeration value="vnd.vidsoft.vidconfer" />
      <xs:enumeration value="vnd.visio" />
      <xs:enumeration value="vnd.visionary" />
      <xs:enumeration value="vnd.vividence.scriptfile" />
      <xs:enumeration value="vnd.vsf" />
      <xs:enumeration value="vnd.wap.sic" />
      <xs:enumeration value="vnd.wap.slc" />
      <xs:enumeration value="vnd.wap.wbxml" />
      <xs:enumeration value="vnd.wap.wmlc" />
      <xs:enumeration value="vnd.wmlscriptc" />
      <xs:enumeration value="vnd.webturbo" />
      <xs:enumeration value="vnd.wfa.wsc" />
      <xs:enumeration value="vnd.wmc" />
      <xs:enumeration value="vnd.wmf.bootstrap" />
      <xs:enumeration value="vnd.wordperfect" />
      <xs:enumeration value="vnd.wqd" />
      <xs:enumeration value="vnd.wrq-hp3000-labelled" />
      <xs:enumeration value="vnd.wt.stf" />
      <xs:enumeration value="vnd.wv.csp+xml" />
      <xs:enumeration value="vnd.wv.csp+wbxml" />
      <xs:enumeration value="vnd.wv.ssp+xml" />
      <xs:enumeration value="vnd.xara" />

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      <xs:enumeration value="vnd.xfdl" />
      <xs:enumeration value="vnd.xmi+xml" />
      <xs:enumeration value="vnd.xmpie.cpkg" />
      <xs:enumeration value="vnd.xmpie.dpkg" />
      <xs:enumeration value="vnd.xmpie.plan" />
      <xs:enumeration value="vnd.xmpie.ppkq" />
      <xs:enumeration value="vnd.xmpie.xlim" />
      <xs:enumeration value="vnd.yamaha.hv-dic" />
      <xs:enumeration value="vnd.yamaha.hv-script" />
      <xs:enumeration value="vnd.yamaha.hv-voice" />
      <xs:enumeration value="vnd.yamaha.smaf-audio" />
      <xs:enumeration value="vnd.yamaha.smaf-phrase" />
      <xs:enumeration value="vnd.yellowriver-custom-menu" />
      <xs:enumeration value="vnd.zzazz.deck+xml" />
      <xs:enumeration value="voicexml+xml" />
      <xs:enumeration value="watcherinfo+xml" />
      <xs:enumeration value="whoispp-query" />
      <xs:enumeration value="whoispp-response" />
      <xs:enumeration value="wita" />
      <xs:enumeration value="wordperfect5.1" />
      <xs:enumeration value="wsdl+xml" />
      <xs:enumeration value="wspolicy+xml" />
      <xs:enumeration value="x400-bp" />
      <xs:enumeration value="xcap-att+xml" />
      <xs:enumeration value="xcap-caps+xml" />
      <xs:enumeration value="xcap-el+xml" />
      <xs:enumeration value="xcap-error+xml" />
      <xs:enumeration value="xcap-ns+xml" />
      <xs:enumeration value="xenc+xml" />
      <xs:enumeration value="xhtml+xml" />
      <xs:enumeration value="xml" />
      <xs:enumeration value="xml-dtd" />
      <xs:enumeration value="xml-external-parsed-entity" />
      <xs:enumeration value="xmpp+xml" />
      <xs:enumeration value="xop+xml" />
      <xs:enumeration value="xsl+xml" />
      <xs:enumeration value="xv+xml" />
      <xs:enumeration value="zip" />
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name="audio-type">
    <xs:restriction base="xs:token">
      <xs:enumeration value="32kadpcm" />
      <xs:enumeration value="3gpp" />
      <xs:enumeration value="3gpp2" />
      <xs:enumeration value="ac3" />
      <xs:enumeration value="AMR" />
      <xs:enumeration value="AMR-WB" />
      <xs:enumeration value="amr-wb+" />
      <xs:enumeration value="asc" />
      <xs:enumeration value="basic" />

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      <xs:enumeration value="BV16" />
      <xs:enumeration value="BV32" />
      <xs:enumeration value="clearmode" />
      <xs:enumeration value="CN" />
      <xs:enumeration value="DAT12" />
      <xs:enumeration value="dls" />
      <xs:enumeration value="dsr-es201108" />
      <xs:enumeration value="dsr-es202050" />
      <xs:enumeration value="dsr-es202211" />
      <xs:enumeration value="dsr-es202212" />
      <xs:enumeration value="eac3" />
      <xs:enumeration value="DVI4" />
      <xs:enumeration value="EVRC" />
      <xs:enumeration value="EVRC0" />
      <xs:enumeration value="EVRC1" />
      <xs:enumeration value="EVRCB" />
      <xs:enumeration value="EVRCB0" />
      <xs:enumeration value="EVRCB1" />
      <xs:enumeration value="EVRC-QCP" />
      <xs:enumeration value="EVRCWB" />
      <xs:enumeration value="EVRCWB0" />
      <xs:enumeration value="EVRCWB1" />
      <xs:enumeration value="example" />
      <xs:enumeration value="G722" />
      <xs:enumeration value="G7221" />
      <xs:enumeration value="G723" />
      <xs:enumeration value="G726-16" />
      <xs:enumeration value="G726-24" />
      <xs:enumeration value="G726-32" />
      <xs:enumeration value="G726-40" />
      <xs:enumeration value="G728" />
      <xs:enumeration value="G729" />
      <xs:enumeration value="G7291" />
      <xs:enumeration value="G72D" />
      <xs:enumeration value="G72E" />
      <xs:enumeration value="GSM" />
      <xs:enumeration value="GSM-EFR" />
      <xs:enumeration value="iLBC" />
      <xs:enumeration value="L8" />
      <xs:enumeration value="L16" />
      <xs:enumeration value="L20" />
      <xs:enumeration value="L24" />
      <xs:enumeration value="LPC" />
      <xs:enumeration value="mobile-xml" />
      <xs:enumeration value="MPA" />
      <xs:enumeration value="mp4" />
      <xs:enumeration value="MP4A-LATM" />
      <xs:enumeration value="mpa-robust" />
      <xs:enumeration value="mpeg" />
      <xs:enumeration value="mpeg4-generic" />
      <xs:enumeration value="ogg" />

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      <xs:enumeration value="parityfec" />
      <xs:enumeration value="PCMA" />
      <xs:enumeration value="PCMU" />
      <xs:enumeration value="prs.sid" />
      <xs:enumeration value="QCELP" />
      <xs:enumeration value="RED" />
      <xs:enumeration value="rtp-enc-aescm128" />
      <xs:enumeration value="rtp-midi" />
      <xs:enumeration value="rtx" />
      <xs:enumeration value="SMV" />
      <xs:enumeration value="SMV0" />
      <xs:enumeration value="SMV-QCP" />
      <xs:enumeration value="sp-midi" />
      <xs:enumeration value="t140c" />
      <xs:enumeration value="t38" />
      <xs:enumeration value="telephone-event" />
      <xs:enumeration value="tone" />
      <xs:enumeration value="ulpfec" />
      <xs:enumeration value="VDVI" />
      <xs:enumeration value="VRM-WB" />
      <xs:enumeration value="vnd.3gpp.iufp" />
      <xs:enumeration value="vnd.4SB" />
      <xs:enumeration value="vnd.audiokoz" />
      <xs:enumeration value="vnd.CELP" />
      <xs:enumeration value="vnd.cisco.nse" />
      <xs:enumeration value="vnd.cmles.radio-events" />
      <xs:enumeration value="vnd.cns.anp1" />
      <xs:enumeration value="vnd.cns.inf1" />
      <xs:enumeration value="vnd.digital-winds" />
      <xs:enumeration value="vnd.dlna.adts" />
      <xs:enumeration value="vnd.dolby.mlp" />
      <xs:enumeration value="vnd.everad.plj" />
      <xs:enumeration value="vnd.hns.audio" />
      <xs:enumeration value="vnd.lucent.voice" />
      <xs:enumeration value="vnd.ms-playready.media.pya" />
      <xs:enumeration value="vnd.mokia.mobile-xmf" />
      <xs:enumeration value="vnd.nortel.vbk" />
      <xs:enumeration value="vnd.nuera.ecelp4800" />
      <xs:enumeration value="vnd.nuera.ecelp7470" />
      <xs:enumeration value="vnd.nuera.ecelp9600" />
      <xs:enumeration value="vnd.octel.sbc" />
      <xs:enumeration value="vnd.rhetorex.32kadpcm" />
      <xs:enumeration value="vnd.sealedmedia.softseal.mpeg" />
      <xs:enumeration value="vnd.vmx.cvsd" />
      <xs:enumeration value="vorbis" />
      <xs:enumeration value="vorbis.config" />
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name="example-type">
    <xs:restriction base="xs:token" />
  </xs:simpleType>

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  <xs:simpleType name="image-type">
    <xs:restriction base="xs:token">
      <xs:enumeration value="cgm" />
      <xs:enumeration value="example" />
      <xs:enumeration value="fits" />
      <xs:enumeration value="g3fax" />
      <xs:enumeration value="gif" />
      <xs:enumeration value="ief" />
      <xs:enumeration value="jp2" />
      <xs:enumeration value="jpeg" />
      <xs:enumeration value="jpm" />
      <xs:enumeration value="jpx" />
      <xs:enumeration value="naplps" />
      <xs:enumeration value="png" />
      <xs:enumeration value="prs.btif" />
      <xs:enumeration value="prs.pti" />
      <xs:enumeration value="t38" />
      <xs:enumeration value="tiff" />
      <xs:enumeration value="tiff-fx" />
      <xs:enumeration value="vnd.adobe.photoshop" />
      <xs:enumeration value="vnd.cns.inf2" />
      <xs:enumeration value="vnd.djvu" />
      <xs:enumeration value="vnd.dwg" />
      <xs:enumeration value="vnd.dxf" />
      <xs:enumeration value="vnd.fastbidsheet" />
      <xs:enumeration value="vnd.fpx" />
      <xs:enumeration value="vnd.fst" />
      <xs:enumeration value="vnd.fujixerox.edmics-mmr" />
      <xs:enumeration value="vnd.fujixerox.edmics-rlc" />
      <xs:enumeration value="vnd.microsoft.icon" />
      <xs:enumeration value="vnd.mix" />
      <xs:enumeration value="vnd.ms-modi" />
      <xs:enumeration value="vnd.net-fpx" />
      <xs:enumeration value="vnd.sealed.png" />
      <xs:enumeration value="vnd.sealedmedia.softseal.gif" />
      <xs:enumeration value="vnd.sealedmedia.softseal.jpg" />
      <xs:enumeration value="vnd.svf" />
      <xs:enumeration value="vnd.wap.wbmp" />
      <xs:enumeration value="vnd.xiff" />
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name="message-type">
    <xs:restriction base="xs:token">
      <xs:enumeration value="CPIM" />
      <xs:enumeration value="delivery-status" />
      <xs:enumeration value="disposition-notification" />
      <xs:enumeration value="example" />
      <xs:enumeration value="external-body" />
      <xs:enumeration value="global" />
      <xs:enumeration value="global-delivery-status" />
      <xs:enumeration value="global-disposition-notification" />

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      <xs:enumeration value="global-headers" />
      <xs:enumeration value="http" />
      <xs:enumeration value="news" />
      <xs:enumeration value="partial" />
      <xs:enumeration value="rfc822" />
      <xs:enumeration value="s-http" />
      <xs:enumeration value="sip" />
      <xs:enumeration value="sipfrag" />
      <xs:enumeration value="tracking-status" />
      <xs:enumeration value="vnd.si.simp" />
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name="model-type">
    <xs:restriction base="xs:token">
      <xs:enumeration value="example" />
      <xs:enumeration value="iges" />
      <xs:enumeration value="mesh" />
      <xs:enumeration value="vnd.dwf" />
      <xs:enumeration value="vnd.flatland.3dml" />
      <xs:enumeration value="vnd.gdl" />
      <xs:enumeration value="vnd.gs-gdl" />
      <xs:enumeration value="vnd.gtw" />
      <xs:enumeration value="vnd.moml+xml" />
      <xs:enumeration value="vnd.mts" />
      <xs:enumeration value="vnd.parasolid.transmit.binary" />
      <xs:enumeration value="vnd.parasolid.transmit.text" />
      <xs:enumeration value="vnd.vtu" />
      <xs:enumeration value="vrml" />
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name="multipart-type">
    <xs:restriction base="xs:token">
      <xs:enumeration value="alternative" />
      <xs:enumeration value="appledouble" />
      <xs:enumeration value="byteranges" />
      <xs:enumeration value="digest" />
      <xs:enumeration value="encrypted" />
      <xs:enumeration value="example" />
      <xs:enumeration value="form-data" />
      <xs:enumeration value="header-set" />
      <xs:enumeration value="mixed" />
      <xs:enumeration value="parallel" />
      <xs:enumeration value="related" />
      <xs:enumeration value="report" />
      <xs:enumeration value="signed" />
      <xs:enumeration value="voice-message" />
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name="text-type">
    <xs:restriction base="xs:token">
      <xs:enumeration value="calendar" />

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      <xs:enumeration value="css" />
      <xs:enumeration value="csv" />
      <xs:enumeration value="directory" />
      <xs:enumeration value="dns" />
      <xs:enumeration value="enriched" />
      <xs:enumeration value="example" />
      <xs:enumeration value="html" />
      <xs:enumeration value="parityfec" />
      <xs:enumeration value="plain" />
      <xs:enumeration value="prs.fallenstein.rst" />
      <xs:enumeration value="prs.lines.tag" />
      <xs:enumeration value="RED" />
      <xs:enumeration value="rfc822-headers" />
      <xs:enumeration value="richtext" />
      <xs:enumeration value="rtf" />
      <xs:enumeration value="rtp-enc-aescm128" />
      <xs:enumeration value="rtx" />
      <xs:enumeration value="sgml" />
      <xs:enumeration value="t140" />
      <xs:enumeration value="tab-separated-values" />
      <xs:enumeration value="troff" />
      <xs:enumeration value="ulpfec" />
      <xs:enumeration value="uri-list" />
      <xs:enumeration value="vnd.abc" />
      <xs:enumeration value="vnd.curl" />
      <xs:enumeration value="vnd.DMClientScript" />
      <xs:enumeration value="vnd.esmertec.theme-descriptor" />
      <xs:enumeration value="vnd.fly" />
      <xs:enumeration value="vnd.fmi.flexstor" />
      <xs:enumeration value="vnd.graphviz" />
      <xs:enumeration value="vnd.in3d.3dml" />
      <xs:enumeration value="vnd.in3d.spot" />
      <xs:enumeration value="vnd.IPTC.NewsML" />
      <xs:enumeration value="vnd.IPTC.NITF" />
      <xs:enumeration value="vnd.latex-z" />
      <xs:enumeration value="vnd.motorola.reflex" />
      <xs:enumeration value="vnd.ms-mediapackage" />
      <xs:enumeration value="vnd.net2phone.commcenter.command" />
      <xs:enumeration value="vnd.si.uricatalogue" />
      <xs:enumeration value="vnd.sun.j2me.app-descriptor" />
      <xs:enumeration value="vnd.trolltech.linguist" />
      <xs:enumeration value="vnd.wap.si" />
      <xs:enumeration value="vnd.wap.sl" />
      <xs:enumeration value="vnd.wap.wml" />
      <xs:enumeration value="vnd.wap.wmlscript" />
      <xs:enumeration value="xml" />
      <xs:enumeration value="xml-external-parsed-entity" />
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name="video-type">
    <xs:restriction base="xs:token">

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      <xs:enumeration value="3gpp" />
      <xs:enumeration value="3gpp2" />
      <xs:enumeration value="3gpp-tt" />
      <xs:enumeration value="BMPEG" />
      <xs:enumeration value="BT656" />
      <xs:enumeration value="CelB" />
      <xs:enumeration value="DV" />
      <xs:enumeration value="example" />
      <xs:enumeration value="H261" />
      <xs:enumeration value="H263" />
      <xs:enumeration value="H263-1998" />
      <xs:enumeration value="H263-2000" />
      <xs:enumeration value="H264" />
      <xs:enumeration value="JPEG" />
      <xs:enumeration value="MJ2" />
      <xs:enumeration value="MP1S" />
      <xs:enumeration value="MP2P" />
      <xs:enumeration value="MP2T" />
      <xs:enumeration value="mp4" />
      <xs:enumeration value="MP4V-ES" />
      <xs:enumeration value="MPV" />
      <xs:enumeration value="mpeg" />
      <xs:enumeration value="mpeg4-generic" />
      <xs:enumeration value="nv" />
      <xs:enumeration value="ogg" />
      <xs:enumeration value="parityfec" />
      <xs:enumeration value="pointer" />
      <xs:enumeration value="quicktime" />
      <xs:enumeration value="raw" />
      <xs:enumeration value="rtp-enc-aescm128" />
      <xs:enumeration value="rtx" />
      <xs:enumeration value="SMTPE292M" />
      <xs:enumeration value="ulpfec" />
      <xs:enumeration value="vc1" />
      <xs:enumeration value="vnd.CCTV" />
      <xs:enumeration value="vnd.dlna.mpeg-tts" />
      <xs:enumeration value="vnd.fvt" />
      <xs:enumeration value="vnd.hns.video" />
      <xs:enumeration value="vnd.iptvforum.1dparityfec-1010" />
      <xs:enumeration value="vnd.iptvforum.1dparityfec-2005" />
      <xs:enumeration value="vnd.iptvforum.2dparityfec-1010" />
      <xs:enumeration value="vnd.iptvforum.2dparityfec-2005" />
      <xs:enumeration value="vnd.iptvforum.ttsavc" />
      <xs:enumeration value="vnd.iptvforum.ttsmpeg2" />
      <xs:enumeration value="vnd.motorola.video" />
      <xs:enumeration value="vnd.motorola.videop" />
      <xs:enumeration value="vnd.mpegurl" />
      <xs:enumeration value="vnd.ms-playready.mediapyv" />
      <xs:enumeration value="vnd.nokia.interleaved-multimedia" />
      <xs:enumeration value="vnd.nokia.videovoip" />
      <xs:enumeration value="vnd.objectvideo" />

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      <xs:enumeration value="vnd.sealed.mpeg1" />
      <xs:enumeration value="vnd.sealed.mpeg4" />
      <xs:enumeration value="vnd.sealed.swf" />
      <xs:enumeration value="vnd.sealedmedia.softseal.mov" />
      <xs:enumeration value="vnd.vivo" />
    </xs:restriction>
  </xs:simpleType>
  <xs:group name="super-types">
    <xs:choice>
      <xs:element name="application" type="application-type" />
      <xs:element name="audio" type="audio-type" />
      <xs:element name="example" type="example-type" />
      <xs:element name="image" type="image-type" />
      <xs:element name="message" type="message-type" />
      <xs:element name="model" type="model-type" />
      <xs:element name="multipa t" type="multipart-type" />
      <xs:element name="text" type="text-type" />
      <xs:element name="video" type="video-type" />
    </xs:choice>
  </xs:group>
  <xs:complexType name="mime-type">
    <xs:group ref="super-types" />
  </xs:complexType>
</xs:schema>

8. MML Schema
<?xml version="1.0" encoding="utf-8"?><xs:schema
  xmlns:xfm="http://www.w3.org/2002/xforms" version="1.0"
  xmlns:xs="http://www.w3.org/2001/XMLSchema"><xs:import
  schemaLocation="http://www.w3.org/MarkUp/Forms/2002/XForms-Schema.xsd"
  namespace="http://www.w3.org/2002/xforms" /><xs:import
  schemaLocation="http://www.w3.org/2001/XMLSchema.xsd"
  namespace="http://www.w3.org/2001/XMLSchema" />
  <xs:include schemaLocation="http://mailmarkup.org/mime.xsd" />
  <xs:element name="mail">
    <xs:complexType>
      <xs:sequence>
        <xs:element maxOccurs="unbounded" ref="session" />
      </xs:sequence>
      <xs:attribute ref="mail-type" use="required" />
      <xs:attribute ref="version" use="required" />
    </xs:complexType>
  </xs:element>
  <xs:attribute fixed="application/mail+xml" name="mail-type" />
  <xs:attribute fixed="1.1" name="version" />
  <xs:element name="session">
    <xs:complexType>
      <xs:sequence>
        <xs:element ref="address" />
        <xs:element minOccurs="0" ref="attachments" />
        <xs:element ref="subject" />

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        <xs:element minOccurs="0" ref="presentation" />
        <xs:choice>
          <xs:element ref="source" />
          <xs:element ref="plain-text" />
          <xs:element ref="markup" />
        </xs:choice>
      </xs:sequence>
      <xs:attribute ref="time-stamp" use="required" />
      <xs:attribute default="en" ref="language" use="optional" />
    </xs:complexType>
  </xs:element>
  <xs:attribute name="time-stamp">
    <xs:simpleType>
      <xs:restriction base="xs:dateTime" />
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="language">
    <xs:simpleType>
      <xs:restriction base="xs:language" />
    </xs:simpleType>
  </xs:attribute>
  <xs:element name="address">
    <xs:complexType>
      <xs:sequence>
        <xs:element maxOccurs="unbounded" name="to" type="agent" />
        <xs:element minOccurs="0" maxOccurs="unbounded" name="copy"
          type="agent" />
        <xs:element minOccurs="0" maxOccurs="unbounded"
          name="blind-copy" type="agent" />
        <xs:element name="from" type="agent" />
        <xs:element ref="reply-to" />
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:element name="reply-to">
    <xs:complexType>
      <xs:simpleContent>
        <xs:extension base="reply-type">
          <xs:attribute ref="alias" use="optional" />
          <xs:attribute ref="public-key" use="optional" />
        </xs:extension>
      </xs:simpleContent>
    </xs:complexType>
  </xs:element>
  <xs:simpleType name="reply-type">
    <xs:restriction base="xs:anyURI">
      <xs:pattern
     value="\c+(\.\c)*@\c+(\.\c)*(\.[a-z]{2,3})|([a-z]{2}\.[a-z]{2})" />
      <xs:pattern value="no-reply" />
    </xs:restriction>
  </xs:simpleType>

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  <xs:complexType name="agent">
    <xs:simpleContent>
      <xs:extension base="email">
        <xs:attribute ref="alias" use="optional" />
        <xs:attribute ref="public-key" use="optional" />
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>
  <xs:simpleType name="email">
    <xs:restriction base="xs:anyURI">
      <xs:pattern
        value="\w+(\.\w)*@\w+(\.\w)*(\.[\w]{2,3})|([\w]{2}\.[\w]{2})" />
    </xs:restriction>
  </xs:simpleType>
  <xs:attribute name="alias">
    <xs:simpleType>
      <xs:restriction base="xs:token" />
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="public-key">
    <xs:simpleType>
      <xs:restriction base="xs:QName">
        <xs:pattern value="[A-Z0-9]+\:\w+"/>
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>
  <xs:element name="attachments">
    <xs:complexType>
      <xs:choice maxOccurs="unbounded">
        <xs:element ref="collection" />
        <xs:element ref="file" />
      </xs:choice>
    </xs:complexType>
  </xs:element>
  <xs:element name="collection">
    <xs:complexType>
      <xs:sequence>
        <xs:element ref="collection-name" />
        <xs:element maxOccurs="unbounded" ref="collection-file" />
        <xs:element minOccurs="0" ref="collection-type" />
        <xs:element ref="collection-description" />
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:element name="collection-name">
    <xs:simpleType>
      <xs:restriction base="xs:token">
        <xs:minLength value="2" />
      </xs:restriction>
    </xs:simpleType>
  </xs:element>

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  <xs:element name="collection-file">
    <xs:simpleType>
      <xs:restriction base="xs:NCName">
        <xs:pattern value="\c+(\.\c+)+"/>
      </xs:restriction>
    </xs:simpleType>
  </xs:element>
  <xs:element name="collection-type" type="mime-type" />
  <xs:element name="collection-description">
    <xs:simpleType>
      <xs:restriction base="xs:normalizedString">
        <xs:minLength value="3" />
      </xs:restriction>
    </xs:simpleType>
  </xs:element>
  <xs:element name="file">
    <xs:complexType>
      <xs:sequence>
        <xs:element ref="file-name" />
        <xs:element ref="file-type" />
        <xs:element ref="file-description" />
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:element name="file-name">
    <xs:simpleType>
      <xs:restriction base="xs:NCName">
        <xs:pattern value="\c+(\.\c+)+" />
      </xs:restriction>
    </xs:simpleType>
  </xs:element>
  <xs:element name="file-type" type="mime-type" />
  <xs:element name="file-description">
    <xs:simpleType>
      <xs:restriction base="xs:normalizedString" />
    </xs:simpleType>
  </xs:element>
  <xs:element name="subject">
    <xs:simpleType>
      <xs:restriction base="xs:normalizedString">
        <xs:minLength value="2" />
      </xs:restriction>
    </xs:simpleType>
  </xs:element>
  <xs:element name="presentation">
    <xs:complexType>
      <xs:sequence maxOccurs="unbounded">
        <xs:element ref="stylesheet" />
      </xs:sequence>
    </xs:complexType>
  </xs:element>

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  <xs:element name="stylesheet">
    <xs:complexType>
      <xs:simpleContent>
        <xs:extension base="xs:anyURI">
          <xs:attribute ref="style-namespace" use="required" />
          <xs:attribute ref="style-type" use="required" />
          <xs:attribute default="screen" ref="media" use="optional" />
        </xs:extension>
      </xs:simpleContent>
    </xs:complexType>
  </xs:element>
  <xs:attribute name="style-type">
    <xs:simpleType>
      <xs:restriction base="xs:token">
        <xs:enumeration value="application/xslt+xml" />
        <xs:enumeration value="text/css" />
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="style-namespace">
    <xs:simpleType>
      <xs:restriction base="xs:ID">
        <xs:pattern value="\w+" />
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="media">
    <xs:simpleType>
      <xs:restriction base="xs:token">
        <xs:enumeration value="all" />
        <xs:enumeration value="aural" />
        <xs:enumeration value="braille" />
        <xs:enumeration value="embossed" />
        <xs:enumeration value="handheld" />
        <xs:enumeration value="print" />
        <xs:enumeration value="projection" />
        <xs:enumeration value="screen" />
        <xs:enumeration value="tty" />
        <xs:enumeration value="tv" />
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>
  <xs:element name="source">
    <xs:complexType>
      <xs:sequence>
        <xs:element ref="source-uri" />
        <xs:element ref="source-type" />
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:element name="source-uri">

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    <xs:simpleType>
      <xs:restriction base="xs:anyURI">
        <xs:minLength value="5" />
      </xs:restriction>
    </xs:simpleType>
  </xs:element>
  <xs:element name="source-type" type="mime-type" />
  <xs:element name="plain-text">
    <xs:simpleType>
      <xs:restriction base="xs:string">
        <xs:minLength value="5" />
      </xs:restriction>
    </xs:simpleType>
  </xs:element>
  <xs:element name="markup">
    <xs:complexType>
      <xs:sequence>
        <xs:choice maxOccurs="unbounded">
          <xs:group ref="complex-blocks" />
          <xs:group ref="simple-blocks" />
          <xs:any namespace="##other" processContents="lax" />
        </xs:choice>
      </xs:sequence>
      <xs:anyAttribute namespace="xmlns" />
    </xs:complexType>
  </xs:element>
  <xs:attributeGroup name="core-attrs">
    <xs:attribute ref="id" use="optional" />
    <xs:attribute ref="style" use="optional" />
    <xs:attribute ref="title" use="optional" />
    <xs:attribute ref="role" use="optional" />
  </xs:attributeGroup>
  <xs:attributeGroup name="core-attrs-uri">
    <xs:attribute ref="id" use="optional" />
    <xs:attribute ref="style" use="optional" />
    <xs:attribute ref="title" use="optional" />
    <xs:attribute ref="role" use="optional" />
    <xs:attribute ref="uri" use="optional" />
  </xs:attributeGroup>
  <xs:attributeGroup name="inter-attrs">
    <xs:attribute default="tl" ref="direction" use="optional" />
    <xs:attribute default="horizontal" ref="orientation"
      use="optional" />
    <xs:attribute default="standard" ref="wrap" use="optional" />
    <xs:attribute default="en" ref="section-language" use="optional" />
  </xs:attributeGroup>
  <xs:attributeGroup name="cell-attrs">
    <xs:attribute default="1" ref="span-column" use="optional" />
    <xs:attribute default="1" ref="span-row" use="optional" />
  </xs:attributeGroup>
  <xs:attribute name="id">

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    <xs:simpleType>
      <xs:restriction base="xs:ID">
        <xs:minLength value="2" />
        <xs:pattern value="\w+" />
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="style">
    <xs:simpleType>
      <xs:restriction base="xs:QName">
        <xs:minLength value="4" />
        <xs:pattern value="\w+\:\w+" />
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="title">
    <xs:simpleType>
      <xs:restriction base="xs:normalizedString">
        <xs:minLength value="2" />
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="role">
    <xs:simpleType>
      <xs:restriction base="xs:token">
        <xs:minLength value="2" />
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="uri">
    <xs:simpleType>
      <xs:restriction base="xs:anyURI">
        <xs:minLength value="5" />
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="direction">
    <xs:simpleType>
      <xs:restriction base="xs:token">
        <xs:enumeration value="tl" />
        <xs:enumeration value="br" />
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="orientation">
    <xs:simpleType>
      <xs:restriction base="xs:token">
        <xs:enumeration value="horizontal" />
        <xs:enumeration value="vertical" />
      </xs:restriction>
    </xs:simpleType>

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  </xs:attribute>
  <xs:attribute name="wrap">
    <xs:simpleType>
      <xs:restriction base="xs:token">
        <xs:enumeration value="standard" />
        <xs:enumeration value="reverse" />
        <xs:enumeration value="none" />
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="section-language">
    <xs:simpleType>
      <xs:restriction base="xs:language">
        <xs:minLength value="2" />
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="refer">
    <xs:simpleType>
      <xs:restriction base="xs:IDREF">
        <xs:minLength value="2" />
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="span-column">
    <xs:simpleType>
      <xs:restriction base="xs:positiveInteger" />
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="span-row">
    <xs:simpleType>
      <xs:restriction base="xs:positiveInteger" />
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="scope">
    <xs:simpleType>
      <xs:restriction base="xs:token">
        <xs:enumeration value="column" />
        <xs:enumeration value="row" />
        <xs:enumeration value="group-column" />
        <xs:enumeration value="group-row" />
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="long-form">
    <xs:simpleType>
      <xs:restriction base="xs:token">
        <xs:minLength value="5" />
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>

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  <xs:group name="complex-blocks">
    <xs:choice>
      <xs:group ref="list-group" />
      <xs:element ref="table" />
      <xs:element ref="section" />
      <xs:element ref="form" />
    </xs:choice>
  </xs:group>
  <xs:group name="simple-blocks">
    <xs:choice>
      <xs:element ref="block-code" />
      <xs:element ref="block-quote" />
      <xs:element ref="citation" />
      <xs:element ref="heading" />
      <xs:element ref="object" />
      <xs:element ref="paragraph" />
      <xs:element ref="separator" />
    </xs:choice>
  </xs:group>
  <xs:complexType name="simple-blocks-type" mixed="true">
    <xs:group minOccurs="0" maxOccurs="unbounded" ref="inline" />
    <xs:attributeGroup ref="core-attrs" />
    <xs:attributeGroup ref="inter-attrs" />
  </xs:complexType>
  <xs:group name="inline">
    <xs:choice>
      <xs:group ref="xfm:Form.Controls" />
      <xs:element ref="short" />
      <xs:element ref="button" />
      <xs:element ref="cite" />
      <xs:element ref="emphasis" />
      <xs:element ref="identifier" />
      <xs:element ref="quote" />
      <xs:element ref="format" />
      <xs:element ref="strong" />
      <xs:element ref="title" />
    </xs:choice>
  </xs:group>
  <xs:group name="object-group">
    <xs:sequence>
      <xs:element ref="object-text" />
      <xs:element ref="object-uri" />
      <xs:element ref="object-type" />
      <xs:group minOccurs="0" maxOccurs="unbounded" ref="inline" />
    </xs:sequence>
  </xs:group>
  <xs:complexType name="inline-base">
    <xs:simpleContent>
      <xs:extension base="xs:string">
        <xs:attributeGroup ref="core-attrs-uri" />
      </xs:extension>

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    </xs:simpleContent>
  </xs:complexType>
  <xs:complexType name="inline-type">
    <xs:simpleContent>
      <xs:restriction base="inline-base">
        <xs:minLength value="1" />
      </xs:restriction>
    </xs:simpleContent>
  </xs:complexType>
  <xs:complexType name="format-type" mixed="true">
    <xs:sequence>
      <xs:element minOccurs="0" maxOccurs="unbounded" ref="format" />
    </xs:sequence>
    <xs:attributeGroup ref="core-attrs-uri" />
  </xs:complexType>
  <xs:group name="list-group">
    <xs:choice>
      <xs:element ref="define-list" />
      <xs:element ref="navigation-list" />
      <xs:element ref="order-list" />
      <xs:element ref="unorder-list" />
    </xs:choice>
  </xs:group>
  <xs:complexType name="nesting-block">
    <xs:choice maxOccurs="unbounded">
      <xs:group ref="complex-blocks" />
      <xs:group ref="simple-blocks" />
    </xs:choice>
  </xs:complexType>
  <xs:element name="define-list">
    <xs:complexType>
      <xs:sequence>
        <xs:element maxOccurs="unbounded" ref="define-item" />
      </xs:sequence>
      <xs:attributeGroup ref="core-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="define-item">
    <xs:complexType>
      <xs:sequence>
        <xs:element maxOccurs="unbounded" ref="define-term" />
        <xs:element maxOccurs="unbounded" ref="definition" />
      </xs:sequence>
      <xs:attributeGroup ref="core-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="define-term">
    <xs:complexType>
      <xs:simpleContent>
        <xs:extension base="xs:normalizedString">
          <xs:attributeGroup ref="core-attrs-uri" />

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          <xs:attributeGroup ref="inter-attrs" />
        </xs:extension>
      </xs:simpleContent>
    </xs:complexType>
  </xs:element>
  <xs:element name="definition">
    <xs:complexType mixed="true">
      <xs:group minOccurs="0" maxOccurs="unbounded" ref="inline" />
      <xs:attributeGroup ref="core-attrs" />
      <xs:attributeGroup ref="inter-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="navigation-list">
    <xs:complexType>
      <xs:sequence>
        <xs:choice minOccurs="0">
          <xs:element ref="heading" />
          <xs:element ref="identifier" />
        </xs:choice>
        <xs:element maxOccurs="unbounded" ref="navigation-item" />
      </xs:sequence>
      <xs:attributeGroup ref="core-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="navigation-item">
    <xs:complexType>
      <xs:choice>
        <xs:element ref="navigation-object" />
        <xs:element ref="navigation-text" />
      </xs:choice>
      <xs:attributeGroup ref="core-attrs" />
      <xs:attribute ref="uri" use="required" />
    </xs:complexType>
  </xs:element>
  <xs:element name="navigation-object">
    <xs:complexType>
      <xs:sequence>
        <xs:element ref="object-text" />
        <xs:element ref="object-uri" />
        <xs:element ref="object-type" />
      </xs:sequence>
      <xs:attributeGroup ref="inter-attrs" />
      <xs:attributeGroup ref="core-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="object-text">
    <xs:simpleType>
      <xs:restriction base="xs:normalizedString">
        <xs:minLength value="3" />
      </xs:restriction>
    </xs:simpleType>

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  </xs:element>
  <xs:element name="object-uri">
    <xs:simpleType>
      <xs:restriction base="xs:anyURI" />
    </xs:simpleType>
  </xs:element>
  <xs:element name="object-type" type="mime-type" />
  <xs:element name="navigation-text">
    <xs:complexType>
      <xs:simpleContent>
        <xs:extension base="xs:string">
          <xs:attributeGroup ref="inter-attrs" />
          <xs:attributeGroup ref="core-attrs" />
        </xs:extension>
      </xs:simpleContent>
    </xs:complexType>
  </xs:element>
  <xs:element name="order-list">
    <xs:complexType>
      <xs:sequence>
        <xs:choice minOccurs="0">
          <xs:element ref="heading" />
          <xs:element ref="identifier" />
        </xs:choice>
        <xs:element maxOccurs="unbounded" ref="list-item" />
      </xs:sequence>
      <xs:attributeGroup ref="core-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="unorder-list">
    <xs:complexType>
      <xs:sequence>
        <xs:choice minOccurs="0">
          <xs:element ref="heading" />
          <xs:element ref="identifier" />
        </xs:choice>
        <xs:element maxOccurs="unbounded" ref="list-item" />
      </xs:sequence>
      <xs:attributeGroup ref="core-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="list-item">
    <xs:complexType mixed="true">
      <xs:choice>
        <xs:group ref="simple-blocks" />
        <xs:group maxOccurs="unbounded" ref="inline" />
      </xs:choice>
      <xs:attributeGroup ref="core-attrs" />
      <xs:attributeGroup ref="inter-attrs" />
    </xs:complexType>
  </xs:element>

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  <xs:element name="form">
    <xs:complexType>
      <xs:sequence>
        <xs:element ref="xfm:model" />
        <xs:element ref="form-body" />
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:element name="form-body">
    <xs:complexType>
      <xs:choice maxOccurs="unbounded">
        <xs:group ref="list-group" />
        <xs:group ref="simple-blocks" />
        <xs:group ref="xfm:UI.Common" />
        <xs:element ref="table" />
      </xs:choice>
    </xs:complexType>
  </xs:element>
  <xs:element name="table">
    <xs:complexType>
      <xs:sequence>
        <xs:element minOccurs="0" ref="head-row" />
        <xs:element maxOccurs="unbounded" ref="table-row" />
      </xs:sequence>
      <xs:attributeGroup ref="core-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="head-row">
    <xs:complexType>
      <xs:sequence>
        <xs:element maxOccurs="unbounded" ref="head-cell" />
      </xs:sequence>
      <xs:attributeGroup ref="core-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="head-cell">
    <xs:complexType mixed="true">
      <xs:choice>
        <xs:group ref="simple-blocks" />
        <xs:group maxOccurs="unbounded" ref="inline" />
      </xs:choice>
      <xs:attribute default="column" ref="scope" use="optional" />
      <xs:attributeGroup ref="cell-attrs" />
      <xs:attributeGroup ref="core-attrs" />
      <xs:attributeGroup ref="inter-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="table-row">
    <xs:complexType>
      <xs:choice maxOccurs="unbounded">
        <xs:element ref="head-cell" />

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        <xs:element ref="table-cell" />
      </xs:choice>
      <xs:attributeGroup ref="core-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="table-cell">
    <xs:complexType mixed="true">
      <xs:choice>
        <xs:group ref="simple-blocks" />
        <xs:group maxOccurs="unbounded" ref="inline" />
      </xs:choice>
      <xs:attributeGroup ref="cell-attrs" />
      <xs:attributeGroup ref="core-attrs" />
      <xs:attributeGroup ref="inter-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="section">
    <xs:complexType>
      <xs:complexContent mixed="false">
        <xs:extension base="nesting-block">
          <xs:attributeGroup ref="core-attrs" />
        </xs:extension>
      </xs:complexContent>
    </xs:complexType>
  </xs:element>
  <xs:element name="block-code" type="simple-blocks-type" />
  <xs:element name="block-quote" type="simple-blocks-type" />
  <xs:element name="citation">
    <xs:complexType mixed="true">
      <xs:group minOccurs="0" maxOccurs="unbounded" ref="inline" />
      <xs:attribute ref="id" use="required" />
      <xs:attribute ref="style" use="optional" />
      <xs:attribute ref="title" use="optional" />
      <xs:attribute ref="role" use="optional" />
      <xs:attributeGroup ref="inter-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="heading" type="simple-blocks-type" />
  <xs:element name="object">
    <xs:complexType>
      <xs:group ref="object-group" />
      <xs:attributeGroup ref="inter-attrs" />
      <xs:attributeGroup ref="core-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="paragraph" type="simple-blocks-type" />
  <xs:element name="separator" type="simple-blocks-type" />
  <xs:complexType name="short-type">
    <xs:simpleContent>
      <xs:extension base="xs:string">
        <xs:attribute ref="long-form" use="required" />

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        <xs:attributeGroup ref="core-attrs-uri" />
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>
  <xs:element name="short">
    <xs:complexType>
      <xs:simpleContent>
        <xs:restriction base="short-type">
          <xs:minLength value="1" />
          <xs:whiteSpace value="collapse" />
        </xs:restriction>
      </xs:simpleContent>
    </xs:complexType>
  </xs:element>
  <xs:complexType name="button-type">
    <xs:simpleContent>
      <xs:extension base="xs:string">
        <xs:attribute ref="refer" use="optional" />
        <xs:attributeGroup ref="core-attrs-uri" />
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>
  <xs:element name="button">
    <xs:complexType>
      <xs:simpleContent>
        <xs:restriction base="button-type">
          <xs:minLength value="1" />
          <xs:whiteSpace value="collapse" />
        </xs:restriction>
      </xs:simpleContent>
    </xs:complexType>
  </xs:element>
  <xs:complexType name="cite-type">
    <xs:simpleContent>
      <xs:extension base="xs:string">
        <xs:attribute ref="refer" use="required" />
        <xs:attributeGroup ref="core-attrs" />
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>
  <xs:element name="cite">
    <xs:complexType>
      <xs:simpleContent>
        <xs:restriction base="cite-type">
          <xs:minLength value="1" />
          <xs:whiteSpace value="collapse" />
        </xs:restriction>
      </xs:simpleContent>
    </xs:complexType>
  </xs:element>
  <xs:element name="emphasis" type="inline-type" />

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  <xs:complexType name="identifier-type">
    <xs:simpleContent>
      <xs:extension base="xs:string">
        <xs:attribute ref="refer" use="required" />
        <xs:attributeGroup ref="core-attrs-uri" />
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>
  <xs:element name="identifier">
    <xs:complexType>
      <xs:simpleContent>
        <xs:restriction base="identifier-type">
          <xs:minLength value="1" />
          <xs:whiteSpace value="collapse" />
        </xs:restriction>
      </xs:simpleContent>
    </xs:complexType>
  </xs:element>
  <xs:element name="quote" type="inline-type" />
  <xs:element name="format" type="format-type" />
  <xs:element name="strong" type="inline-type" />
  <xs:element name="title" type="inline-type" />
  <xs:annotation>
    <xs:documentation>
    Mail Markup Language, MML, is a method of structuring, defining, and
    describing content and data in email for a variety of reasons.
    Please refer to http://mailmarkup.org for more information.  First
    implementation begun by Austin Cheney on 12 October 2007.
    </xs:documentation>
  </xs:annotation>
</xs:schema>

9. References
   [CSS]
         Bos B, Celik T, Hickson I, Lie H. "Cascading Style Sheets Level
         2 Revision 1 (CSS 2.1) Specification", W3C Candidate
         Recommendation, W3C, Stanford, Opera, July 2007.
         <http://www.w3.org/TR/CSS21/>

   [FORMAT]
         Crocker D. "Standard for the Format of ARPA Internet Text
         Messages", University of Delaware, August 1982.
         <http://www.ietf.org/rfc/rfc822.txt>

         Resnick P. "Internet Message Format", RFC 2822, Qualcomm, April
         2001.  <http://www.ietf.org/rfc/rfc2822.txt>

   [HTML5]
         Hickson I. "HTML 5", WHATWG Draft Recommendation, WHATWG,
         August 2008.  <http://whatwg.org/html5>


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   [HTTP]
         Fielding R, Gettys J, Mogul J, Frystyk H, Masinter L, Leach P,
         Berners-Lee T. "Hypertext Transfer Protocol -- HTTP/1.1", RFC
         2616, UC Irvine, Compaq, W3C, MIT, Xerox, Microsoft, June 1999.
         <http://www.ietf.org/rfc/rfc2616.txt>

   [IANA]
         Reynolds J, Postel J. "Assigned Numbers", STD 2, RFC 1700,
         USC/Information Sciecnes Institut , October 1994.
         <http://www.ietf.org/rfc/rfc1700.txt>

   [IMAP]
         Crispin M. "Internet Message Access Protocol, Version 4rev1",
         RFC 3501, University of Washington, March 2003.
         <http://www.ietf.org/rfc/rfc3501.txt>

   [KAON]
         Gabel T, Sure Y, Voelker J. "Kaon -- An Overview: Karlsruhe
         Ontology Management Infrastructure", University of Karlsruhe,
         April 2004.
         <http://kaon.semanticweb.org/main_kaonOverview.pdf>

   [KEYWORDS]
         Bradner S. "Key words for use in RFCs to Indicate Requirement
         Levels", RFC 2119, Harvard University, March 1997.
         <http://www.ietf.org/rfc/rfc2119.txt>

   [MIME]
         Freed N, Borenstein N. "Multipurpose Internet Mail Extensions
         (MIME) Part One: Format of Internet Message Bodies", RFC 2045,
         Innosoft, First Virtual, November 1996.
         <http://www.ietf.org/rfc/rfc2045.txt>

         Freed N, Borenstein N. "Multipurpose Internet Mail Extensions
         (MIME) Part Two: Media Types", RFC 2046, Innosoft, First
         Virtual, November 1996.  <http://www.ietf.org/rfc/rfc2045.txt>

         Moore K. "MIME (Multipurpose Internet Mail Extensions) Part
         Three: Message Header Extensions for Non-ASCII Text", RFC 2047,
         University of Tennessee, November 1996.
         <http://www.ietf.org/rfc/rfc2047.txt>

         Nelson S, Parks C, Mitra. "The Model Primary Content Type for
         Multipurpose Internet Mail Extensions", RFC 2077, LLNL, NIST,
         WorldMaker, January 1997.
         <http://www.ietf.org/rfc/rfc2077.txt>

         Freed N, Klensin J. "Media Type Specifications and Registration
         Procedures", RFC 4288, Sun Microsystems, December 2005.
         <http://www.ietf.org/rfc/rfc4288.txt>


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         Freed N, Klensin J. "Multipurpose Internet Mail Extensions
         (MIME) Part Four: Registration Procedures", RFC 4289, Sun
         Microsystems, December 2005.
         <http://www.ietf.org/rfc/rfc4289.txt>

   [NAMESPACES]
         Bray T, Hollander D, Layman A, Tobin R. "Namespaces in XML 1.0
         (Second Edition)", W3C Recommendation, Textuality, Contivo Inc,
         Microsoft, Univerity of Edinburgh and Markup Technology Ltd,
         August 2006.  <http://www.w3.org/TR/REC-xml-names/>

   [OWL]
         McGuinness D, Harmelen F. "OWL Web Ontology Language Overview",
         W3C Recommendation, Stanford University, Vrije Universiteit,
         February 2004.  <http://www.w3.org/TR/owl-features/>

   [POP3]
         Myers J, Rose M. "Post Office Protocol - Version 3", RFC 1939,
         Carnegie Mellon, Dover Beach Consulting Inc, May 2006.
         <http://www.ietf.org/rfc/rfc1939.txt>

   [RDF]
         Klyne G, Carroll J, McBride B. "Resource Description Framework
         (RDF): Concepts and Abstract Syntax", W3C Recommendation, Nine
         by Nine, Hewlett Packard Labs, February 2004.
         <http://www.w3.org/TR/rdf-concepts/>

   [SMTP]
         Klensin J. "Simple Mail Transfer Protocol", RFC 2821, AT&T
         Laboratories, April 2001.
         <http://www.ietf.org/rfc/rfc2821.txt>

   [SYMBOLISM]
         Mead G, "Mind, Self & Society From the Stand-Point of A Social
         Behaviorist", University of Chicago Press, 1947. [BOOK]

   [URI]
         Berners-Lee T, Fielding R, Masinter L. "Universal Resource
         Identifiers (URI): Generic Syntax", RFC 3986, W3C/MIT, Day
         Software, Adobe Systems, January 2005.
         <http://www.ietf.org/rfc/rfc3986.txt>

         Hoffman P, Masinter L, Zawinski J. "The mailto URL Scheme", RFC
         2368, Internet Mail Consortium, Xerox Corporation, Netscape
         Communications, July 1998.
         <http://www.ietf.org/rfc/rfc2368.txt>

         Mealling M, Denenberg R. "RFC3305 - Report from the Joint
         W3C/IETF URI Planning Interest", RFC 3305, W3C URI Interest
         Group, August 2002.  <http://www.ietf.org/rfc/rfc3305.txt>


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   [W3C]
         Connolly D, Masinter L. "The 'text/html' Media Type", RFC 2854,
         W3C, AT&T, June 2000.  <http://www.ietf.org/rfc/rfc2854.txt>

   [W3C-XML-SCHEMA]
         Fallside D, Walmsley P. "XML Schema Part 0: Primer Second
         Edition", W3C Recommendation, IBM, October 2004.
         <http://www.w3.org/TR/xmlschema-0/>

         Walmsley P. "Definitive XML Schema", Prentice Hall, December
         2001.  [BOOK]

   [WAI-ARIA]
         Cooper M, Schwerdtfeger R, Seeman L, Pappas L. "Accessible Rich
         Internet Applications (WAI-ARIA) Version 1.0", W3C Working
         Draft, W3C, IBM, UB Access, Society for Technical
         Communication, August 2008.  <http://www.w3.org/TR/wai-aria/>

   [WCAG]
         Caldwell B, Cooper M, Guarino R, Vanderheiden G. "Web Content
         Accessibility Guidelines 2.0", W3C Candidate Recommendation,
         University of Wisconsin-Madison, W3C, Google Inc., Trace R&D
         Center, April 2008.  <http://www.w3.org/TR/WCAG20/>

   [XFORMS]
         Boyer J. "XForms 1.0 (Third Edition)", W3C Recommendation, IBM,
         October 2007.
         <http://www.w3.org/TR/2007/REC-xforms-20071029/>

   [XML]
         Bray T, Paoli J, Sperberg-McQueen C, Maler E, Yergeau, F.
         "Extensible Markup Language (XML) 1.0 (Fourth Edition)", W3C
         Recommendation, Textuality, Microsoft, W3C, Sun, August 2006.
         <http://www.w3.org/TR/REC-xml/REC-xml-20060816.xml>

   [XSL]
         Berglund A. "Extensible Stylesheet Language (XSL) Version 1.1",
         W3C Recommendation, IBM, December 2006.
         <http://www.w3.org/TR/xsl/>

   [XHTML]
         Pemberton S, Austin D, Axelsson J, Celik T, Dominiak D,
         Elenbaas H, Epperson B, Ishikawa M, Matsui S, McCarron S,
         Navarro A, Peruvemba S, Relyea R, Schnitzenbaumer S, Start P.
         "XHTML 1.0 The Extensible HyperText Markup Language (Second
         Edition)", W3C Recommendation, CWI, W3C, Grainger, Opera
         Software, Microsoft, Openwave Systems, Philips Electronics,
         Netscape/AOL, Panasonic, Applied Testing and Technology,
         WebGeek Inc., Oracle, SAP, Sony Ericsson, August 2002.
         <http://www.w3.org/TR/xhtml1/>


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   [XHTML2]
         Axelsson J, Birbeck M, Dubinko M, Epperson B, Ishikawa M,
         McCarron S, Navarro A, Pemberton S. "XHTML 2.0", W3C Working
         Draft, Opera Software, x-port.net, Websense, W3C, Applied
         Testing and Technology, WebGeek Inc., CWI, July 2006.
         <http://www.w3.org/TR/xhtml2/>

10. Acknowledgements
   I would like to thank all those wonder people who supported me,
   without which this would not have been possible.  Some of those
   people are Dustin Askins, Don Hay, Craig Hoersten, David McCarty,
   Stephen Marshall, the technology and legal executives of Sabre,
   and my wife Melissa.

11. Author's Address

   Austin Cheney
   User Interface Technologist, Travelocity
   3150 Sabre Drive
   Southlake, TX 76092

   PHONE: (682) 605-1000






























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